Duplicate Territory records can be merged from the Territory Maintenance window. 

Note    It is not possible to reverse the merge of two territories.

From the Receivables module:

1. Navigate to the Maintenance menu and select 5. Territories.

The Territory Maintenance window is displayed.2. Select the master territory from the list. The master territory is the record you wish to retain.

3. Click Merge.

The Merge Territories window is displayed.4. In the Slave Territory field, enter the Code or Name of the territory you wish to merge.

5. Review the Master and Slave Territories, then check the Merge checkbox.

6. Click Okay to perform the merge.