A family of Microsoft relational database management systems designed for ease of use.
This is a Database I created about 10 years ago, it’s on a shared drive so multiple people can use it,
This is the WRONG configuration and may be, at least partially, a source of your problem.
EVERY multi-user application NEEDS to be split between a back end (the tables) and a front end (everything else). The back end should be on the shared network drive and the front end install on each user's PC.
You might consider reconfiguring as described and seeing if that helps your problem.