probsummary stuck

Hello,

One of my customer has a very strange issue.

After DB upgrade from SQL 2012 to SQL 2017 the probsummary table only gets stuck (Cannot view, insert or update any record) on random intervals (some times every 1 day sometimes every 3 days) issue being resolved after application restart.

Issue is not reproducible and the system has deep customization

Service Manager Version --> 9.63

OS --> Windows

any guidance?