popline | Popline is an HTML5 Rich-Text-Editor Toolbar | Editor library

You are emptying the line element empty with each fetch, but it looks like you want to empty it only for the first time, the best way I can think of is to use some sort of flag so that you know it's the first time. $(document).ready(function(){ var lineselects = document.getElementsByName("line"); lineselects.forEach($line => $line.addEventListener('click', popLines)); }); function popLines(){ fetch('ajax0.php',{method:'post'}) .then( r=>r.json() ) .then( json=>{ if ( $( '#line' ).data('first-time') != 'no' ) { line.innerHTML=''; $( '#line' ).data('first-time', 'no'); } Object.keys( json ).forEach( key=>{ let obj=json[ key ]; line.append( new Option( obj.line, obj.line ) ); }) }) };

Your problem is that you are using global variables in Flask - Not recommended at all, and that causes your issue. You see, when a user signs in, you programmed the code to put as the "name_user" to the user who just signed in. that's why it changes the user every time a new user logs in to the site. Luckily you are using flask-login so you can simply use current_user.Name to get the name of the user who is currently logged in.

So in summary:

insted of: