Mobile Issue.

[callforjudgement]

I think I can explain this: most mobile providers use a rotating pool of IPs, and you therefore don't always get the same one when you connect.

You probably just randomly happened to end up on an IP that a banned user had used at the time of their ban / in the recent past; it's unlikely, but possible. Then when you moved onto a new IP things started working again.

Many sites have a policy to expire IP bans after a while in order to stop things like this happening.