Recover old number

[KenAdams]

I have an old PAYG sim that has not been used it some time and I have recently discovered has expired.  If I call the number I am getting a message saying the number is not available so it does not seem to have been reassigned to anyone yet.  

I have called customer support who have said they have no record of the number and so it must have gone into the pool of deactivated numbers and is forever lost.  I asked her to confirm if the numbers are never reassigned and she said yes, but this seems contrary to what I have read elsewhere.

The problem is that this number is tied as an authentication method to some accounts that I really need to regain access to.  I am perfectly willing to pay a fee to get this number back again, but the lady on the call said this wasn't possible for expired number.

Before I give up all hope I wonder if anyone else been in this situation and managed to get it resolved? 

Thanks

[madasaf1sh]

@KenAdams 

It depends on how long it was last used, and yes numbers are reused how quickly depends on the system which picks up a number a random form the pool.

[Bambino · Accepted solution]

@KenAdams Try calling customer service again in the hope that you'll get someone who knows what they're talking about. Call 0800 032 1402 from any phone or numbers here: Guide: Coronavirus Community Help and Support 
When it comes to the reason you are calling, stay silent for 15 seconds and you will be taken to the keypad options.
Press 2 for Everything Else
Press 5 for More Options
Press 7 for Anything Else which will put you though to someone.
Say 'Upgrade', 'Lost/Stolen', or 'Fraud' if the suggestion above doesn't get you through.
Best time to call is 8 am.
You can also reach O2 via social media:
Facebook (https://o2uk.co/O2CFB), Twitter (https://o2uk.co/O2CTW), or Instagram (https://o2uk.co/O2CIG)

[Tiuzzi-89]

Called o2 today in the hope of getting my bf old mobile number back .... £ 100 fee to get it back... £ 100... are they gone mad?! Can someone confirm this? Cheers