Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> a22e2e9e5799789479f9d4dae4bfd5e1aec0eebd322ed442582b1d8c5d8c1aa4:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^