Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 9fd749fd8fa22a7cbb294ab6b1d8fb7602ab84829cc4e2cff8c4fe16cd0d271f:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^