No facial hair allowed for facial expressions study?

I was just 20 minutes into a study that required me to making smiling faces on camera while it shows pictures on screen. The thing is there was 20 minutes of brain teasing cognitive tests that took place before this part of the study and THEN it drops the bombshell of

-No glasses allowed

-No hats allowed

-No…facial hair allowed?

If that’s the rule, then fine but why would it not let me know that until so deep into the study? I have a short well groomed beard but I didn’t wanna take any chances and returned the study anyway. Anyone else get tripped up by this one?