UK players are moving away from phone bill deposits, which often had low limits...
https://www.strobe-bookmarks.win/uk-players-used-to-top-up-casino-accounts-via-phone-bill-deposits-but-they
UK players are moving away from phone bill deposits, which often had low limits like £30 per transaction. Instead, they now prefer Faster Payments and mobile wallets for quicker, simpler deposits