I've set the Google Merchant Center sales tax to only collect in Indiana. I've set the sales tax in Shopify to only collect in Indiana as well. However, every couple of days the settings in Merchant Center switch back to showing that I'm collecting sales tax in ALL of the states and not just Indiana. I manually change them all back and, sure enough two days later they've changed back again. Anybody have any idea why this would be happening?
If you are using Shopify free shopping app, go to the app > settings > tax > make sure to choose manual submission.
When it changes automatically it means a app that is connected via content API is changing it.
Ah, that's annoying, I thought it was the same as shipping settings that you could enable manual submission.
I recommend contact Shopify support and Google Ads support, to find out what the issue is. Most likely the current app is bugged. Alternatively use a different app. That only submits the feed.