j2 Global Communications "Slammed" my telephone number and sold it to XO Communications Internet

We couldn't figure out what was wrong with our telephone service until a technician came to my home to physically check the line.  The line was fine so after calling the technical support/billing/etc. at Verizon I found out that J2 Global Communications had "slammed" (stolen) my telephone number and sold it to XO Communications...my "new" provider!  I had no part in this and I am suprised that this can be done without my knowledge.  Now Verizon can not stop the disconnect order unless it comes from XO communications.  I've reported to CA Utilities Commission but I've wasted hours of my day and who knows what they plan on charging me...since I've never spoken to J2 or XO. How can this happen?