Mesa Cannot be Clicked

I'm new to the endgame and recently finished clearing my first Mesa. I got the precursor tablet at the end and talked to Doryani after. Based on what I see online, the Mesa should now be open for me to insert a precursor tablet, but it's not clickable. It's just a dead object. Is there anything I can do for this bug, or is it not a bug, and I'm just missing something?

Thanks!