Why does Coach a Fighter say my code is invalid?
Almost always a missing trailing exclamation mark or wrong capitalisation. After that: the tutorial is not finished, or the code was already redeemed on that account.
Troubleshooting
Four causes, ranked by how often they are the actual problem.
Updated
Both live codes end in "!" — Update1! and Release!. The exclamation mark is part of the code, not punctuation in the article you copied it from.
This is by far the most common cause. If a code is rejected, check this before anything else.
Codes are case-sensitive. "update1!" is not "Update1!". Typing them by hand from a video is where this usually goes wrong.
The Codes button lives in the main interface, and the main interface is not fully available until the intro sequence is done. New players frequently conclude the button does not exist when they simply have not reached it yet.
Each code works once per Roblox account. There is no cooldown between different codes, so redeem both in a row — but neither will pay twice on the same account.
Expiry. Neither code has expired — the game has shipped two codes total and both still work, so "the code is dead" is almost never the answer right now.
If you are certain the code is typed correctly and the tutorial is done, the next place to check is the official Discord announcements channel, in case a code was rotated without any tracker site noticing.
FAQ
Almost always a missing trailing exclamation mark or wrong capitalisation. After that: the tutorial is not finished, or the code was already redeemed on that account.
No. Only two codes have ever existed and both are still working.