UK casino players have moved from using phone bill deposits, which often capped...

https://wiki-room.win/index.php/Why_Were_Phone_Bill_Deposits_Popular_with_Casual_Players%3F

UK casino players have moved from using phone bill deposits, which often capped at around £30 per transaction, to Faster Payments and modern mobile methods. These newer options let players add as little as £10 quickly and securely