How to Fix Dolphin XP008 Fail to Cut Flat Key?

One customer gave feedback that Dolphin XP008 did not support his key. His key looks the same as the supported one that should be cut by side C.
ori key
ori key type
supported key type
Here is the
His key is flat key, which is different from bit key.
supported key types

Use XP007 Machine, or Xhorse Automatic Machines.