Transaction

[Error Code: 1101] cadence runtime error Execution failed:
error: underflow
  --> 6dbf12dd31605696de553261e40e0fe5dcbf9eba5e66d8a5f349287f3d0b7e8a:16:8
   |
16 |         let total: UFix64 = SwapConfig.ScaledUInt256ToUFix64(res) - 0.2
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^