I've been having this issue for 5 days now, it is impacting my business.
Squarespace is not helping, and I can't contact Instagram as a user. I have submitted an error with Instagram but who knows where this goes.
Customers will not buy if they have roadblocks in the purchase funnel. It's seriously impacting my sales.
My only option if this does not resolve is to leave Squarespace.
I suggest that Squarespace take this more seriously and contact Instagram directly.
We need an answer.