Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 388f193b3aafc846e07f5e51a3a0e00026dc0a0a17ce5b43e5b3f9e6a41ebfa3:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^