Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> ed20c0ca557a367cb5dd5dcb0bd2ba9a4fc2f1e7123ead8ce4c9902a08f31c81:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^