if ( do something ) else don't do it JQuery

I want to change some text and data-attribute value in my HTML, explicitly the modal-footer when I am on login page(section in the modal). It works however once I leave that page the change it remains, which I don't want. I want it to change back to default once I leave that page.

How can I do that?

function showPages() {

let $aBtnShowPages = $(".btnShowPage");
// this is an array
for (let i = 0; i < $aBtnShowPages.length; i++) {

    $aBtnShowPages.eq(i).click(function () {

        // Hide the pages
        let $aPages = $('.page');
        for (let j = 0; j < $aPages.length; j++) {
            $aPages.eq(j).css("display", "none");;
        }

        let $sDataAttribute = $(this).attr("data-showThisPage");
        //console.log($sDataAttribute);
        $($sDataAttribute).css("display", "block");
        if ($sDataAttribute === '#login') {
            $('.modal-footer span').text("Don't have a LimeLINE account yet?");
            $('.modal-footer a').text('Signup').attr("data-showThisPage", "#signup_general");
        } else {
            // what should I write here
        }
    });

}

}

the HTML part:

   <div class="container">
        <div class="row">
            <!--Signup Modal Structure -->
            <div id="modal" class="modal">
                <div class="modal-content">
                    <section id="signup_general" class="page">
                        <div class="row">
                            <a href="#!" class="col s6 modal-action modal-close">
                                <i class="fa fa-times-circle-thin fa-2x" aria-hidden="true"></i>
                            </a>
                        </div>
                        <div class="row">
                            <a class="col s12 waves-effect waves-light btn-large social facebook">
                                <i class="fa fa-facebook"></i> Sign up with facebook</a>
                        </div>
                        <div class="row">
                            <a class="col s12 waves-effect waves-light btn-large social google">
                                <i class="fa fa-google"></i> Sign up with google</a>
                        </div>
                        <div class="row">
                            <span class="col s12 center">
                                or
                            </span>
                        </div>
                        <div class="row">
                            <a class="col s12 waves-effect waves-light btn-large social lime btnShowPage" data-showThisPage="#signup_email">
                                <i class="fa fa-envelope"></i>Sign up with email</a>
                        </div>
                    </section>
                    <!--Signup with email section -->
                    <section id="signup_email" class="page">
                        <div class="row">
                            <div class="col s12 center">
                                <span>Signup with</span>
                                <a href="#!" class="">Facebook</a>
                                <span>or</span>
                                <a href="#!" class="">Google</a>
                            </div>
                        </div>
                        <div class="row">
                            <span class="col s12 center">
                                or
                            </span>
                        </div>
                        <form class="col s12">
                            <div class="row">
                                <div class="input-field col s12">
                                    <input id="first_name" type="text" class="validate">
                                    <label for="first_name">First Name</label>
                                </div>
                            </div>
                            <div class="row">
                                <div class="input-field col s12">
                                    <input id="last_name" type="text" class="validate">
                                    <label for="last_name">Last Name</label>
                                </div>
                            </div>
                            <div class="row">
                                <div class="input-field col s12">
                                    <input id="email" type="email" class="validate">
                                    <label for="email">Email</label>
                                </div>
                            </div>
                            <div class="row">
                                <div class="input-field col s12">
                                    <input id="mobile_number" type="number" class="validate">
                                    <label for="mobile_number">Mobile Number</label>
                                </div>
                            </div>
                            <div class="file-field input-field">
                                <div class="btn lime">
                                    <span>File</span>
                                    <input type="file">
                                </div>
                                <div class="file-path-wrapper">
                                    <input class="file-path validate" type="text" placeholder="Upload your profile image">
                                </div>
                            </div>
                            <div class="row">
                                <a class="col s12 waves-effect waves-light btn-large lime">
                                    </i>Sign up</a>
                            </div>
                        </form>
                    </section>
                    <section id="login" class="page">
                        <div class="row">
                            <a class="col s12 waves-effect waves-light btn-large social facebook">
                                <i class="fa fa-facebook"></i>Log in with facebook</a>
                        </div>
                        <div class="row">
                            <a class="col s12 waves-effect waves-light btn-large social google">
                                <i class="fa fa-google"></i> Log in with google</a>
                        </div>
                        <div class="row">
                            <span class="col s12 center">
                                or
                            </span>
                        </div>
                        <form class="col s12">
                            <div class="row">
                                <div class="input-field col s12">
                                    <input id="email" type="email" class="validate">
                                    <label for="email">Email</label>
                                </div>
                            </div>
                            <div class="row">
                                <div class="input-field col s12">
                                    <input id="mobile_number" type="number" class="validate">
                                    <label for="mobile_number">Mobile Number</label>
                                </div>
                            </div>
                            <div class="row">
                                <a class="col s12 waves-effect waves-light btn-large lime">
                                    </i>Log In</a>
                            </div>
                        </form>
                    </section>
                    <div class="row">
                        <div class="col s12 modal-footer">
                            <span class="col s9">Already have a LimeLINE account?</span>
                            <a class="col s3 btnShowPage" data-showThisPage="#login">Login</a>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </div>