Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> a30c95e772c5e70e00abc959fcaa5b9e4a4fe5dde09f1d4dc7ceda1c774ee91a:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^