I am in the exact same boat, I have a 3.7 cumulative and 3.67 in the major with a 310 v+q on the GRE and I only got accepted to one school, which I will de declining due to cost. I also have a pretty good breadth of volunteer experiences and extracurriculars from my undergrad. I am on 2 waitlists but it doesn't look great for either. It is frustrating to feel like you are a decently qualified candidate and then get heartbroken by this process.
I am planning on taking 2 years to build up my resume even more, then reapply for Fall of 2021. I really don't know what else to do because like you my GPA is set in stone at this point and I don't think I will be able to significantly improve my GRE scores. Thank you for sharing your experience, it made me feel a little bit better knowing there are others in a similar situation as I am.