Hi @Sajith Gopalakrishnan Hema ,
For event error 3760, please try to restore database from backup then reconnect the database in Central Administration.
For event error 6398, I noticed there are three timer jobs failed, please provide detailed error message, I will find some similar posts for your reference:
(1)App State Update timer job is aimed to retrieve and apply updated information on apps from the SharePoint Store, including the availability of updates and disable information.
We could turn off this timer job in Central Admin if you aren't using any Store Apps,this will solve the issue.
(2) User Profile Service Application - Feed Cache Full Repopulation Job handles the repopulation of feed cache for users, If this fails you’ll probably not see any social feeds working. It will not impact to the server.
(3)The function of Product Version Timer Job is putting the updated version information from the SharePoint Server on to the SharePoint Databases.
If the job doesn’t run, then there may be an issue on product version mismatch during certain server level operation. And it will not impact the update of SharePoint Production.
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