Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 9fc6b5615ec8eb3a9efcbcfa7bb0df42bd35fb02d8e2f07b8bbc43bcda781e7d:16:32
   |
16 |                                 let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^