CODE_ERROR

There is an error in the cadence code of this transaction.

[Error Code: 1101] cadence runtime error Execution failed: error: underflow --> 79c8c4ff77ad7359c0247e84100b8c5123553015d8f9baf4e12e8a8fa7891c2c:23:212 | 23 | let token1Vault <- UsdcUsdtSwapPair.swapToken1ForToken2(from: <- (token0Vault as! @FiatToken.Vault));let vaultOut <- FlowSwapPair.swapToken2ForToken1(from: <- token1Vault);earn = earn + vaultOut.balance - cur;flowTokenVault.deposit(from: <- vaultOut) | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^