I can‘t join the gac anymore

That sounds really frustrating, especially when you're in the middle of a battle. Here are a few things you can try to get back into the Grand Arena Championship (GAC):

1. Check for Updates: Ensure that your game is up to date. Sometimes bugs like this can be fixed with a patch, so it’s worth checking for any available updates.
2. Clear Cache: If you're playing on a mobile device, clearing the app's cache might help. This can sometimes resolve issues where the game isn't responding properly.
3. Switch Networks: Even though you've tried with and without WiFi, you could try switching between different networks or using mobile data if possible, just to rule out any connection issues.
4. Contact Support: If the error persists, it might be a server-side issue that you can’t fix on your end. Contact the game's support team, and let them know about the error you’re experiencing. Providing them with any error codes or screenshots could help them identify the issue faster.
5. Be Patient: If this is a widespread issue, the developers might already be working on a fix. Keep an eye on official channels or forums for any updates.

I hope one of these steps works for you and that you're able to get back into the fight soon!