Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 10b1e44fea09814a3be0dc2a2bedb515fb6e4b9a1b7d6da485fb4cb20ad8905e:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^