Why unlock USDT tokens?

Why should I unlock USDT tokens before purchasing Token States tokens?

Token purchase contract on Token States follow ERC-20 standard. For a smart contract like Token States to be able to interact with an ERC-20 token, you must approve the amount of tokens this contract can use from your wallet.

To do this, you must first do an ‘unlock’ transaction, which allows you to specify how many USDT tokens this contract can use. In Token States, you unlock a token permanently, so you won’t need to do it again the next time you buy TS tokens.

This allowance can be revoked at any moment. If you do so, you will have to allow it again if you wish to buy new tokens in the future.