Unlike you I'll probably never get a chat restriction based on my behavior in-game up to now, your reactions are making it all too clear why this happened, why not confess? This is starting to feel like a troll thread meant to try to confuse people
(had that feeling when I first read it tbh).
The only way you can be reported that I know of for not talking is if you also don't use or respond to pings (assuming you didn't cause other problems, like feeding intentionally, or stealing buffs from your JG out of spite, things like that), I'm not entirely sure if that's accurate though.
This may just be an automation issue where enough people report you over time for not communicating at all. If you were at least pinging & being a team player you should be fine. If so you should be able to resolve it as others have said by sending in a support ticket or something.
Might want to chill out, so far it feels like you're lying.