Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> b23d61a5e888809f1f37df049c52a8f2afe9e8ed32b2e7e60fed4c9c7ffb5572:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^