Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 423bf68e63ce47ea251d8f02c8f84a9a8f7bc79bba350af8a0c7fe950fd6f61f:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^