Unable to login in OJS any user with correct ID pass without even upgrade

Hello,
i have been using Ojs since past 4 years and all a sudden users cant login we did update as well to anyother version still on version 3.1 since pas 6 months but its not working need urgent help

Hi @webdev,

Are you able to check your PHP error log? that might provide some clues to what is happening.

-Roger
PKP Team