weird bug where if-else statment doesnt work properly

I have a really weird bug in my program. Im working with linked list in this program. The ead->next does show up as nullptr but the if statement is skipped. The weird part is that it doesn't go to the else statement after that. I got this info from stepping through the debugger. I marked the part of the function that holds the bug. Any reason why this is happening? I thought there was something wrong with the compiler but my program was tested on my class server and had the same problem.

void linked::deletetype(string what, node* ead) {
    if (ead == nullptr) {
        return;
    }
    else if (ead->type == what && ead->previous == nullptr) {
        // it enters here
        if (ead->next == nullptr) {// this is suppose to be true but it skips
            ead == nullptr;
            head == nullptr;
        }
        else {//even though it skips the if statment doesn't go to the else statement.
            ead = ead->next;
            ead->previous = nullptr;
            head = ead;
        }
     // programs completely skips over else
    }
    else if (ead->type == what&&ead->next!=nullptr) {
        ead->previous->next = ead->next;
        ead->next->previous = ead->previous;
    }
    else if (ead->type == what && ead->next == nullptr) {
        ead = ead->previous;
        ead->next = nullptr;
        tail = ead;
    }

    deletetype(what, ead->next);
}