This sounds like a good question for our Restaurants team, @AlouettePDX
They can take a look at your account with you to help shine a light here, as they can look at your account alongside you to pinpoint what's causing this behavior with the Open Tables integration. Please reach out by phone or email when you have a moment by logging into your Square account and heading here.
P.S. Welcome to the Seller Community
Community Moderator, Square
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