Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 1bd00f1f8fdfc754a6aada0c2b36ed8a7c008ffcdb724cc21db0d02ac49d69ed:15:8
   |
15 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^