Ipads in Guided Access "rebooting" and needing the lock code to get back into guided access

Hello - We have 10 IPAD 2019 12.9s - we are using it for OpenTable in our restaurant. Over the last several days the Ipads keep restarting, we then have to go to the individual restaurants and use the security code to get through the initial screen. It's almost like maybe updates are being applied and then the system restarts, when this happens it's asking our employees for the lock code, which we don't want them to have.

I'd also like to have something similar to remote desktop for the ipads, for me to solve these things remotely as our restaurants are in different geographical areas.