Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> bc92add6bd28baebd925fdf1ef8b0c9902cb0b33b0ca184fcdfc8aee9f0e84e1:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^