What the search question means
Stake’s public Help Center says a valid affiliate code may be added within 24 hours after account creation. That makes the account age and whether another code is already attached the first things to check.
What to do next
If more than 24 hours have passed, or another referral/promotion is already attached, contact Stake support and ask which offer is currently attached to the account. MainGame cannot change an account’s eligibility.
Keep the offers separate
For new accounts, use the main Stake promo-code page. For a missing field, read Stake code troubleshooting.
Related: read the full offer guide.