I too was a victim of 123-Reg...
Just days after taking my hard-earned for a 3-year renewal, they announced they were "migrating" (sic) their email system. Buried in the announcement email was the bit about no longer supporting catch all emails. Which I used.
Tried to query this with their passive-aggressive support creatures from Hell who first said no problem, then agreed "problem" - but no refund. All the while their documentation still says "Catch-all email forwarding is a great feature which comes with any 123 Reg domain name."
So, after many years with 123-Reg, I moved the last domain I had with them to join its friends at TSOHost - cheaper, good support and with catch-all forwarding. Should have done so a long time ago. And I'm doing a credit card chargeback for the money they took, knowing they were about to break the product but not telling the customer.
I was so miffed that I went to Trustpilot to give them a 1-star rating and I see that quite a few other long-time (now ex-) customers are doing the same. Strangely, there has been a rash of 5-star "invited" ratings, all saying stuff like "resolved my issue. There is as no problem at 123-Reg". So I guess that's OK then.
123-Reg now appear to have done a reverse ferret on the catch all emails, but only if you pay them twenty-something quid a year for a mailbox. Good luck to them with that...