I also encountered this problem. If I try to save the search, the error "Validation errors exist on criteria" appears, although the necessary criteria are selected.
But if I click the search button, the search works well, only I can't change the set of columns. Please help me solve the problem.
Here are the parameters of my system:
OsTicket v1. 14. 2 (cba6035) - Latest version
Apache Web Server SOFTWARE
The MySQL Version 5.5.62
PHP version 5.6.40