Exchange 2019 unable to open internal user calendar error "Could not be updated"

Dear All,

Users are not able to view calendar that reside on specific server. Whenever they access check the free/busy on calendar either from owa/ outlook client, it will prompt error "could not be updated"

in order to resolve this, user mailbox need to migrate to other server and this is very troublesome and waste of time. it might be issue with the exchange server and what other log we can review to dig further.