MP rester error

Hi,

It’s been working fine, but recently, an error has occurred. What has changed recently?

from mp_api.client import MPRester
mpr = MPRester("my key")
mp_entries = mpr.get_entries_in_chemsys(["Li", "O"])

raise MPRestError(
mp_api.core.client.MPRestError: REST query returned with error status code 404 on URL https://api.materialsproject.org/thermo/?_fields=entries&chemsys=Li-O&_limit=333 with message:
Response {"message":"no Route matched with those values"}

Please update your mp-api client (pip install -U mp-api). Also please check this forum for similar questions before posting. Thanks!