Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 82d8da1c74f5bde473aa417a2aa53a4a3d21a0eed84e9e7c1ab2eeb6b17cc502:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^