Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 24c1993ef1c44ea6b35ea19f2ffd4bed64e7b5fb68124f3fb47cf72c2ee0b120:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^