Assume that you use Microsoft SQL Server 2014 or 2016 AlwaysOn Availability Groups and have permission to change ownership of an availability group. After the owner of the availability group is dropped from SQL Server, you can't change the ownership of the availability group. For example, when you try to change ownership of the availability group by executing the ALTER AUTHORIZATION ON AVAILABILITY GROUP statement, the execution fails, and a dump file is generated.
This problem was first fixed in the following cumulative updates for SQL Server:
Note After you install this update, you can take ownership of an availability group even after the owner is dropped.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.