Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 83ac5afea69e2788fdf2cfa261e8d9e5bfe20c36198c9f1ef001a726bcbdbbe9:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^