Vision client username and password problem

How to reset the username and password in ignition vision client

Welcome, you haven't stated which version you are on.

Did you explicitly mean in a Vision client or for a Vision client?

https://docs.inductiveautomation.com/display/DOC81/Managing+Users+and+Roles

If in then there is the user management component.

If for, then there is a section in the gateway you can edit, also described in the above link.

This assumes you are using the standard user/roles security and not another feature such as IDP.