Inaccurate shipping costs (due to inconsistent shipping costs between your feed and the checkout pages on your website)
The shipping costs in your product data don't match the shipping costs on the checkout pages on your website.".
I have checked and found everything OK in my shipping profiles, at GMC, it has been mentioned that the shipping costs are "handled by Shopify", so why the error is occurring and why google issuing account suspension warning emails?
What solution are you using to generate/ submit your feed to merchant centre at present?
The most obvious solution is clearly to correct the 'shipping' value in the feed you are using and make sure the rules it has to calc the shipping value for given product to a given destination
Or it may be better for you to to remove 'shipping' completely from the feed and build your zones in Adwords. So you can match these rules to how your shipping is calculated at checkout also, perhaps using some variables from the product feed .. e.g. shipping_weight and/ or price/ sale_price
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