Unknown Potcar Warning

pymatgen/io/vasp/inputs.py:1856: UnknownPotcarWarning: POTCAR with symbol Pr has metadata that does not match any VASP POTCAR known to pymatgen. The data in this POTCAR is known to match the following functionals: ['PBE_52', 'PBE_54', 'unvie_PBE_52']
When post-processing results from a TbO2 relaxation, I get the same UnknownPotcarWarning and pymatgen interprets the Tb ions as Ce when printing output structure data, plotting DOS, etc.

How should this behaviour be handled since the post-processing of VASP results is being affected in the case of TbO2.

Can results generated by pymatgen modules on raw VASP output data be interpreted as the same when this warning is not present? Does this affect the integrity of the results in a general sense?

I have received the same error, but the odd thing is is that it was part of a Gibbs run where it had to run several deformations. 6 of the 7 deformations completed successfully while one didn’t and exited with this error. Even in this case, there is a lot of VASP output indicating that it has run for a while so it is not clear why this error is being raised and why it happens inconsistently.