Approval transaction troubleshooting#

If an approval transaction is not working as expected, there are steps you can take.

Multiple approval requests#

Some tokens require an existing approval to be revoked before a new one can be submitted. Approving such a token without first revoking the old approval results in being prompted again.

Follow How to revoke a token approval, then submit your swap again. You will be asked to approve the token and set a spending limit once more, which should then succeed.

Any token can occasionally hit this issue — revoking and re-approving usually resolves it. Certain stablecoins and tokens with non-standard approval logic are the most common cause.

Approval or signature request not prompting your wallet#

If requests from CenturionDEX do not appear in your wallet:

  • Incompatible wallets: Some smart-contract wallets may not receive transaction prompts.
  • Connection: Disconnect and reconnect your wallet; make sure your wallet app is updated; or try a different wallet app.
  • Browser: Clear the cookies/cache for the CenturionDEX web app, try a different browser, or do a hard refresh (Control/Command + Shift + R).
  • Network: Make sure you are connected to Centurion (chain ID 286); see How to switch networks.
  • Amount: If you approved a certain amount, try transacting slightly below it.

Setting a token approval amount#

The approval amount controls how much of a token a contract can access:

  • Exact amount: Approves exactly what you want to swap. Most secure, but every swap needs a new approval (and a network cost).
  • Unlimited: Approves unlimited access to reduce future approvals. More convenient but riskier — only use it with trusted dapps after verifying the URL and contract.
  • Balanced: Approves more than you need now, but not unlimited (for example, approving 750 of a token to swap 500). Balances convenience and safety.

Tips: prioritize security, match the amount to how often you transact, review approvals periodically, and remember every approval or revocation has a network cost.