Hi there!

Sorry for your issue.

It seems not an issue related with our product but Joomla itself. Did you update your Joomla version, recently?

I can see related discussion about it on Joomla forum. Please check the following:

https://forum.joomla.org/viewtopic.php?f=708&p=3656600

https://www.akeeba.com/news/1750-do-not-install-the-joomla-4-1-1-and-3-10-7-updates.html

Hope this helps anyways!

Best Regards

YES, it's Joomla bug this time. @Rashida have fully right. I had this same on one of my sites. Easy to fix.

Offcial solution: https://docs.joomla.org/Special:MyLanguage/J3.x:After_going_to_4.1,1_or_3.10.7_some_users_can%27t_login_anymore

My own: Download Joomla 3.10.8 update and upload on your Joomla via FTP - then you should be able to login. Then update database in Joomla admin. That's all.