Hey @Danil,
I'm not aware of any universal issue preventing all PAYG customers from buying a pack. As @Anonymous mentioned, when you post on the community you're primarily addressing a forum of fellow Three customers. I'd recommend to have a chat with customer services, and they can help solve or escalate it if there's an issue with your My3 account.
Thanks,
Jonathan
Mod tip! The author of a post can hit 'Accept as Solution', to highlight a reply that helped solved their query.
