Interactions between Budget Control and Phone Lock
Global Settings phone locking options
From the "Phone Locking Options" tab in the Global settings page, you can exclude specific numbers or range of numbers from the phone lock feature.
These exclusions are not related to Phone Lock exclusions. If a phone has been locked by the user or by the administrator through Phone Lock, Budget Control can't unlock it.
You can enter one entry for each row. You can use the character "!" to allow any sequence of digits (i.e. 9! for any number starting with 9). You can use the character "." to allow any single digit (i.e. 90.. for any 4 digit number starting with 90).

Phone locking associated to a specific budget
During Budget assignment, there's a specific tab called "Phone Locking", where you can decided whether to lock all the IP phones associated to a budget when it is overcome, and whether to unlock them at the end of the budget period.
This page is also useful to troubleshoot phone locking issues, because it shows a list of the phones linked to the budget which cannot be locked by Phone Lock, if any. If everything is ok, the list is empty. To fill the list, press the Refresh link.

Note: please check the phone locking options requirements in the Product Configuration article.
Note: to unlock a locked phone after the budget has been overcome, the administrator can access to user assigned budget and uncheck above "lock phone when budget is reached" flag.