I hope this works: https://support.apple.com/guide/safari/manage-cookies-sfri11471/mac, fingers crossed it helps you!

I am having the exact same issue. I've allowed a full day in between even opening the website and still it says try again after a short rest!

it finally worked on my phone after weeks

It took me forever to finally figure out how to do it, but it worked! Thank you so much!

Hey I'm experiencing more issues, does anyone know if it's something from dndbeyond? (also I have cleared cookies and such already.)

It's broken.. again

Seems to be working again