CenturionDEX Support
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What is an approval transaction?#

An approval transaction gives a specified spender permission to transfer up to a selected amount of your CRC-20 token. It does not move the token by itself, but the spender can use the allowance later under the contract's rules.

How it works#

A CRC-20 allowance has three parts:

  • Owner: your account.
  • Spender: the contract allowed to transfer tokens.
  • Amount: the maximum remaining allowance.

When you swap a CRC-20 token or add liquidity, the Centurion Protocol contract may need an allowance before it can pull the token into the transaction. Native CTN does not use a CRC-20 approval. WCTN does because it is a CRC-20 token.

An approval and a swap are separate onchain actions, although a smart-account wallet may display or submit them as one batch. Read each underlying action rather than assuming a single confirmation has only one effect.

Step-by-step#

  1. Open the intended swap or liquidity action in CenturionDEX.
  2. Verify the token contract, amount, pool version, and network.
  3. When prompted, review the spender address in your wallet.
  4. Choose an exact or limited allowance when the interface and wallet support it.
  5. Confirm the approval and wait for it to finalize.
  6. Submit the swap or liquidity transaction separately if it was not batched.
  7. After use, review and remove allowances you no longer need through a trusted Centurion-compatible approval interface.

Exact versus unlimited approval#

An exact approval limits exposure to the intended amount but may require another transaction for future use. A very large approval is more convenient, yet it creates continuing risk if the spender is compromised, upgraded, or malicious.

Changing an allowance also costs CTN because it is an onchain transaction. Disconnecting CenturionDEX from your wallet does not remove the allowance.

Common issues#

  • Approval succeeded but swap fails: market movement, token restrictions, or insufficient CTN can still stop the swap.
  • Repeated approval prompt: the approved spender or amount may differ from the route currently selected.
  • Allowance appears but cannot be used: some tokens require resetting an existing allowance before changing it.
  • Unexpected approval request: cancel and verify the website, token, spender, and transaction data.
  • NFT permission shown instead: CRC-721 and CRC-1155 operator approvals can be broader than a fungible allowance.

Stay safe#

Treat approval as access to your assets. Never approve a contract from an unsolicited message, fake claim page, or copied support site. Review the spender and amount, and never share a recovery phrase, private key, or password.

Related#