SyncSwap is a decentralized exchange and liquidity hub for routine DeFi trading, but most failed swaps come from the wallet, network, token contract, or pool—not from the swap interface itself. The fastest fix is to match the chain, preserve the native gas token, verify the token contract, and treat every quote as temporary.
Why does SyncSwap show “insufficient gas”?
“Insufficient gas” means your wallet lacks enough of the network’s native token to complete the transaction, even when the token you are selling has a healthy balance.
On ZKsync Era, for example, USDC cannot normally pay the transaction fee; you need ETH on ZKsync Era unless the interface offers a supported gas-payment alternative. Do not spend the wallet down to its final fraction of native gas. Keep a buffer for the approval transaction and the swap itself.
Also check that the wallet is connected to the chain holding the funds. ETH on Ethereum mainnet, Linea, or another network is not the same balance as ETH on ZKsync Era. ZKsync Era is an Ethereum Layer 2 rollup, so its network and balances remain distinct from Ethereum mainnet even though the environments are closely related. ZKsync Era’s official documentation describes that execution model.
Which balance is missing when the token appears in your wallet?
The missing balance is often on the wrong network or belongs to a different contract with the same ticker.
Switch the wallet to the network selected in the swap screen, then compare the token’s contract address—not merely its symbol—with the asset you intend to trade. A fake USDC, bridged version, or token on another chain can appear familiar while remaining unusable in the selected pool. SyncSwap’s documentation currently lists ZKsync Era, Linea, Scroll, Sophon, and Creator Chain among its live deployments; availability and liquidity can differ by network. The project’s network list is the relevant reference.
Once the chain and contract are correct, refresh the balance and request a new quote in syncswap . Do not reuse an old quote after switching networks or reconnecting the wallet.
What makes a quoted swap fail with “price impact too high”?
“Price impact too high” means the trade is too large for the available pool depth at the quoted rate.
Reduce the trade size, split it into smaller transactions, or choose a route with deeper liquidity. For stablecoins or closely pegged assets, a Stable Pool is generally more suitable; for volatile or long-tail assets, a Classic or Aqua Pool may provide the appropriate route. A Range Pool can have excellent pricing inside its active range but little usable liquidity outside it.
Do not solve a thin pool by setting slippage to an extreme value. You may force execution at a materially worse price, especially with a low-volume token. Fees matter too: SyncSwap’s documentation states that Classic Pools charge a 0.1% trading fee, with 0.07% going to liquidity providers and 0.03% to the protocol. The official fee breakdown gives the published split.
Has approval succeeded but the swap still reverted?
A successful approval only gives the router permission to spend the selected token; it does not guarantee that the later swap will succeed.
Common causes are a stale quote, an expired deadline, insufficient output after market movement, a changed balance, or a token with transfer rules the pool does not handle cleanly. Reopen the token selector, confirm the amount, request a fresh quote, and inspect the wallet’s transaction details before signing.
If the approval was for less than the amount now being sold, approve the remaining amount. If the token uses rebasing, transfer fees, blacklists, or other nonstandard behavior, check its documentation before retrying. Never approve an unfamiliar contract merely because the transaction is labeled “approval”; compare the spender address with the protocol’s published deployment information.
How can you clear a transaction that stays pending?
A pending transaction needs an on-chain status check before you submit anything again.
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Open the transaction hash in your wallet activity.
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Open that hash in the explorer for the selected network.
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Compare the explorer status with the status shown in the interface.
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Reconnect the wallet if the explorer shows success but the interface still shows pending.
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Resubmit the swap only when the explorer shows that the original transaction failed or was dropped.
Submitting a duplicate while the first transaction remains pending can create confusion and, with rapidly changing prices, an unintended second trade. If the wallet offers a speed-up or replacement transaction, use it only for the same nonce and intended action.
Who should use something other than SyncSwap?
SyncSwap is the wrong tool when you need fiat deposits, custody, guaranteed execution, limit orders, deep liquidity for an obscure pair, or a chain it does not currently support.
Use a regulated centralized exchange for fiat conversion and custody, a limit-order venue for exact execution prices, or a chain-native DEX or aggregator when the required asset has deeper liquidity elsewhere. If your funds are still on another network, use that network’s official bridge before troubleshooting the swap itself.
For everyone else, the failure pattern is narrow: fund gas on the correct chain, verify the token contract, approve the correct spender, refresh the quote, reduce size when liquidity is thin, and confirm the transaction on-chain.