Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 1f715fe4659f3bdbb1ca934f4fbbf5896fbe51a7dec8385fade13e95d4fe1b3c:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^