The QR code says "Pairing expired," and your first instinct is to scan it again. But you are worried that scanning again will create a duplicate connection, or even produce two transactions in one action. Relax. That worry is unnecessary, but you are guessing in the wrong direction.
A leading global cryptocurrency platform,suitable for both beginners and experienced traders.
New user benefit: 20% off trading fees upon registration!！
Scanning again will not create a duplicate connection. But if you do not clean up before scanning again, the old zombie session can prevent the new code from working. This is not a duplicate connection problem. It is a session conflict that causes the new connection to be rejected directly.
Why an "Expired" QR Code Cannot Be Used Again
Behind every WalletConnect QR code is a one-time pairing token, or pairing ID. A countdown starts as soon as the token is generated. Once it expires, the server simply marks it as invalid.
More importantly, once a pairing token has been scanned one time, the ID becomes invalid whether the connection succeeded or not. The WalletConnect specification clearly states: "Scanning a QR code multiple times is not allowed." When the server receives a second scan request, it returns an error instead of helping you reconnect.
The Correct Way: Manually Clean Up and Refresh
If you already see a "Pairing expired" or "Pairing expired" message, follow these three steps. This has nothing to do with duplicate connections. You are using a new token to create a new pairing.
Step 1: Close the QR code popup on the DApp page
Click the X in the top right corner of the popup and close it. Do not refresh the page. Just close the popup.
Step 2: Open the wallet on your phone and clear old sessions
Open the wallet app you used to scan the code, such as MetaMask, Trust Wallet, or ImToken:
- Find the "Connected sites" or "WalletConnect sessions" list. It is usually in settings, or near the WalletConnect feature entry.
- Look for any pending connection related to the current DApp and delete it. Usually you can swipe left or long press to delete.
Completion standard: there is no pending entry for this DApp in the connected sites list.
High risk: if you do not clear the old session and just refresh the QR code and scan again, your mobile wallet may think you are using a new token to start a "second connection request" while the old session is still hanging in the background. At that point, the wallet may pop up a prompt asking you to "choose an existing session or create a new session." If your hand is too fast and you choose the old one, the new code is wasted. This is similar to how repeated scanning can create duplicate binding entries and cause authentication failure in certain MFA binding logic.
Step 3: Regenerate the QR code and scan it
Go back to the DApp page and click the "Regenerate QR code" or "Refresh" button. This is not the browser refresh button. It is the refresh QR code button built into the page. After the new code appears, use the scan function in your mobile wallet to scan it again.
A leading global cryptocurrency platform,suitable for both beginners and experienced traders.
New user benefit: 20% off trading fees upon registration!！
Apply the Same Logic to Similar Situations
When you see a "QR code expired/invalid" message in these scenarios, the handling logic is the same: close the popup, clear old sessions, and refresh the QR code:
- Scanning a QR code on an exchange website to log into a wallet, such as the Binance Web3 wallet login
- Scanning with a mobile wallet to connect to a DeFi app such as Uniswap or PancakeSwap
- Using Trust Wallet to scan a code and connect to a Web3 login entry for a game
The only exception: if you never scanned the code at all, but the QR code itself says it has expired, the countdown simply ran out. In that case, you do not need to clear sessions. Just click the refresh button to generate a new code and scan it.
How to verify that the operation is complete: after scanning, your phone shows a connection confirmation popup. Tap "Connect." On the computer, the DApp page should show your wallet address in the top right corner instead of a "Connect Wallet" button. If the address appears but the page functions are not working, wait 3-5 seconds and refresh the page once. You do not need to go through the entire scanning process again.
