Permissions to Contracts

When you use Dapps you give permissions for them to spend from your wallet, on your behalf. The problem with this over time is if one of those Dapps gets hacked or someone else takes over, they'll be able to drain your wallet using those permissions.

For this reason it's important to revoke permissions periodically or move your assets to a wallet that you never use on any Dapp.

Each network scanner has functionality to revoke permissions.

Ethereum Network - etherscan.io Token Approval

IoTeX Network - iotexscan.io Token Approval Checker

Other Tools you can use:

Token Audit Contract Sniffer