You're currently being hit by Hextech Crafting Restrictions.
The length of time you're restricted from earning loot is relative to two things:
- Severity of punishment. You won't earn loot for the duration of your punishment, be it a temporary suspension or a chat restriction.
- Signs of reform. Once your punishment has ended, you'll continue to be restricted from earning loot until you're recognized to have made significant progress in amending your past behavior.
You'll work towards regaining access to Hextech Crafting rewards by playing games and not exhibiting toxicity in these games. Time may also be a factor, but the number of games you go through is by far the more important indicator, and simply taking a break from League or switching accounts won't remove your Hextech Crafting restrictions.