Searching user account not display

Nextcloud version: 13.0.1
Operating system and version : Centos 7
Apache or nginx version: Apache/2.4.6
PHP version:
PHP 5.6.31 (cli) (built: Sep 14 2017 18:12:46)
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The issue you are facing:
There are some specific user account for example user1, user2, user3, user4, user5, those users same problem when searching user information like email address via typing 3 letters that should appeared but its not displaying and keeps loading and nothing happened. I used one Desktop computer to investigate the problem. The error occurs on Linux Ubuntu and Windows 7,10. for specific account only. see screenshot below


I tried other account example user6, user7 and user8 its working fine email address appeared immediately in the same desktop computer

Is this the first time you’ve seen this error? (Y/N): Yes this is first time



using chrome its working fine not sure if compatability issue on firefox mozilla