If you do a test on the Dial Plan page, you will see that Voxalot is routing an 883xxxxxxxxxxxx number to a Voxbone IP address. So either the routing IP has changed or it is not working.
However, the suggestion by Ron should work perfectly, and any provider on the iNUM list can also be tested and used :
iNum - One number for the world - iNum Providers
Just be sure to match the replacement number in your Dial plan with the format expected by the provider you are using.
For example, if you are using Callcentric as the outbound provider, the number must be in the format [00883xxxxxxxxxxxx].