Start with the most common causes before resetting the wallet, restoring from a recovery phrase, or trusting a support message.
The words are incomplete, out of order, misspelled, or from a different wallet
A local MetaMask password is being confused with the recovery phrase
Accounts created after the first account have not been re-added after restore
The restored wallet is on the wrong network or account view
The phrase was exposed to a fake support site, form, bot, or remote helper
Multiple wallet backups were mixed together during restore
A MetaMask restore can look incomplete when additional accounts, imported private-key accounts, hardware wallet accounts, custom networks, or manually imported tokens have not been re-added
A MetaMask browser or extension update can reload the wallet, reset connected-site permissions, lock popups, or leave stale RPC/token data until the profile refreshes