There are constituencies applied to contact records in Sphere. You need to remove one or more constituency from many records. Aside from doing one record at a time, you want to remove the constituency from multiple or all records at once, possibly through a batch function.
There is not a batch removal of constituencies available in Sphere. The constituencies will need to be removed one at at time.
If the records do not have any financial transactions on them:
Export the records out of Sphere
Perform a batch delete of the records
Import the records
This would allow the records to be within Sphere without the constituency.