Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 77c8fc7c8a6baed00021d4755aee0dea18a07a7bc5a94bf93ec6db2b75887c2e:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^