severdia
That's not the stance just can't replicate your issue and it really doesn't make much sense. There is not enough information to go off of here. You are positive a brand new error PHP Fatal error: Uncaught Error: Non-static method Misc::currentURL() cannot be called statically
with a new timestamp is logged when you run the upgrade script? Or is the only thing that happens is the upgrade failed notification and that's it?
Have you checked your other logs (general server logs, webserver error logs, PHP error logs, MySQL/MariaDB error logs, osTicket System Logs, Browser Console logs, etc.) for any related errors?
Cheers.