I've tried reaching out to a number of places for support, including StackExchange and other forums and nobody has replied in the past 3 days. Is HMAC verification really this difficult to work with? I just want to be able to continue development on ...

Building this Shopify app with Flask that interfaces with Facebook, but when Facebook redirects me through the callback I'm not getting an HMAC parameter for verification.This is the validation function: def is_valid_request(params, hmac_signature): ...