How to maintain phone number

My phone service was disconneted in error on the 28th. This internet and phone package is for my small business. I am being told my phone and fax numbers are gone and not retreivable?  How do I get my numbers back and reconnect reassign service? [Edited: "Personal Information"] office, [Edited: "Personal Information"] fax.  Do I go to a competitor to get my numbers back for my business? Xfinity is destroying my business.