Unspecified error when entering referral code

Unspecified error when entering referral code

Hey, I didn’t played Pokémon Go since 2016. I just reactivated my account this morning and tried to enter my girlfriend’s referral code. She changed it three times, I tried via the link, copying it, etc… nothing coming up. I just have a pink square appearing in the middle of my screen that says « Error ».

By the way: we were both showing online, and yes I entered the right code.

Please help Niantic…