Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> c37b54057b3dcfa417f45bde1f3b939af79ca22fde6fa432c5f4ea8a08a28cbc:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^