Revoke tokens approval
To remove a dApp access to your wallet's tokens, you can revoke approvals previously granted. An easy way to do it would be to use Revoke, for example.
- Head over Revoke, click "Connect wallet" and select Metamask.
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Metamask will open - connect your target account.
Click the "Revoke" button on the right side for the token of your choice.
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Sign the transaction on Metamask, and wait for confirmation on Revoke's UI.
After a few seconds, the targeted entry should disappear from the UI - you're done!
Note
Revoking means changing the Approval amount back to 0 - it's a transaction you'll have to sign, and it'll therefore consume some gas.