Anyone had any luck haggling O2 on their SIM-only deal?

Chordeiles

As we went into 2025 I was "responsible" for three O2 Sim-only contracts (self, wife, granddaughter) and was already fed up of the new "approved by regulator" annual increases.  Then final straw was that granddaughter was running out of data (she regularly does her homework away from wi-fi because of sporting commitments) so I called O2 asking them to match one of their new customer deals for her.  They flatly refused.  So now all three of us are with Lebara and happy we switched.  

Weirdly two of us got (pitiful) refunds for remaining days of the month in which we switched ( I had expected nothing), but my wife was billed a further month after her switch, followed shortly after by a (smaller) refund.  Failed to negotiate their awful website to query this, so sent a letter (confident they will ignore it so will ask bank to refund the DD).  bills and refunds are variously to or from "O2" or "Telefonica" according to our bank statement, if that wasn't confusing enough the website insisted she link her "O2" account to her "Virgin" account (she didn't have one !).  All in all I feel we are better off without this bunch of idiots.

Chordeiles

Got to laugh.  My wife just got a call which she assumed was a(nother) scam, told them to go away.  Thick South Asian accent that she couldn't properly understand.  I asked if they said who they were and she said "Auto complaints, I think".  I reckon that was "O2 complaints".  Well, they made it really difficult for us to contact them, time for them to write a letter !
In the meantime we continue to get masses of emails from them, trying to get us to upgrade to the latest Samsung 'phone etc. - following the cancel link led me quite easily (after receiving a code by SMS) to a page where I could select my preferences.  But if I deselected all three spam options then the "save preferences" button was greyed-out !  That's clearly illegal, and when our visitors have gone and I have a spare moment I'll bring that to the attention of the information commissioner.