Remove a DID
From VoIP.ms Wiki
Removing a DID from your account is a task that you can do from your main portal, please go to the Finances tab and then click DID Billing. From this page, you can cancel number(s). Remember this process can not be reversed, you need to be sure that you will no longer need the number. You will be prompted with the following screen.
If you are porting out your DID please wait until it is working with the new provider and then delete it from your VoIP.ms account. Please do not forget to check the box: Check here if you ported this number to another network. Once you no longer have a DID, your account won´t generate any charges, except when you make a call. Remember that you can still use your VoIP.ms account for outgoing calls without having a DID.