this question gets asked quite often as unfortunately it's not possible to move a mobile number within the same network.
Therefore: Get yourself a cheap Pay As You Go SIM from any other network (I managed to find an EE one on eBay for 99p delivered with credit on). However you can get PAYG SIM's from almost anywhere but bare in mind that youmaybe required to top it up first hence my going the eBay route.
1. Call 789 & request a PAC(Porting Authorisation Code) for your Virgin Mobile PAYG number that you wish to keep.
2. Once you have your other providers SIM up & running, port your Virgin Mobile number onto it using the PAC (once you do this your Virgin SIM will "die" & you'll lose any credit that may remain so you might want to use it up first).
3. Once established on the new network. Request a PAC from your new provider then port your number back onto your Virgin Pay Monthly SIM.
Sounds like a right palava but in reality I have done this myself within a week from start to finish.
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