Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> d57cbdf29406e4a92b9ffbfbf51ae85dd168e0b5b8e8eef3bc21537e1599028f:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^