If condition with roles Add group

Can you help me?...What is wrong here? if i use only a condition this works perfect.

This dont work

function jeffery_join_vendor_group( $user_id, $role, $old_roles ) {
$current_user = new WP_User(wp_get_current_user()->id);
$user_roles = $current_user->roles; 
foreach ($user_roles as $role) {

if( $role == 'customer' ){   
    groups_accept_invite( $user_id, 140 );
}
if ($role == 'shop_manager'){
groups_accept_invite( $user_id, 140 );
}
 }}
  add_action( 'set_user_role', 'jeffery_join_vendor_group', 11, 3 );

This works

  function jeffery_join_vendor_group( $user_id, $role, $old_roles ) {

if( $role == 'customer' ){   
    groups_accept_invite( $user_id, 140 );
}

  }
  add_action( 'set_user_role', 'jeffery_join_vendor_group', 11, 3 );