Correct format for energies in extxyz?

[yzjin]

I am trying to convert my own data into the extxyz format, but it seems like nequip is unable to recognize the energy field. I have put the energies into the info['energy'] and info['free_energy'] of the ase.Atoms object I constructed, similar to the sitraj.xyz file provided in the colab tutorial. However, I keep getting the runtime error for missing the energy:
RuntimeError: The field key total_energy is not present in this dataset

Is there something I missed? The header in my extxyz file looks like this:

Lattice=.... Properties=species:S:1:pos:R:3:forces:R:3 energy=-20 free_energy=-20 pbc="T T T"

[yzjin]

It seems like in such cases the key mapping should also be specified as follows:

key_mapping:
  free_energy: total_energy

Perhaps the tutorial config needs to be edited, but that's how I solved this problem.