And what does that mean exactly ?
When am I able to watch the Forum again on my phone ?
It means that at some point, someone with the IP address that your phone has now was using that IP address to spam (from the looks of it, a lot of your IP addresses were used in the past to send out email spam, so I would guess that would be it).
You will be able to come on the forum again via your phone when your phone's IP address changes to an IP address that doesn't have a history of abuse. So if you can connect to a network instead of just using your data plan to browse the forum, that would do the trick.