Depending on where you're based it is a little bit different. Shopify has a guide for how to set up taxes for all regions here. Could the order have come from a different country or area where tax is different by any chance?
I saw this was an issue from 2019 but I'm having this exact issue today when trying to bill a customer for a custom item I made for them.
My situation is exactly the same: when I start the order taxes appear to be added, but once I add the customer information on the right then the tax doesn't get applied and when I click on the "tax" line it pops open to give me the option, but it won't let me apply. I'm not shipping this item to them - I will be hand delivering it. When my orders come in for me through my Shopify online store the tax is being collected properly so I know I have the tax set up for that correctly. I live in Texas and I am selling this to a Texas customer. Very frustrated. Any solution in 2021 for me to see how to do this step by step?
This is strange for sure. Without taking a closer look at the tax settings of your store it's very difficult to figure out why this might be happening. This is something which you would need to reach out to our support team about who can assign it to the right team to look into. We’re not able to provide account-specific support via the Shopify Community at this time, we’d be happy to continue assisting you through live chat, email, or callback. Please visit our support team here and log in to your account to create a support request. Once you are talking to a support advisor and verified your account they can assist you with this.
It could also be worth double-checking and going over your tax settings as per the help guides here too to make sure everything is correct!
I am having this issue as well. It does not seem to be setting-related. Unless I enter a specific address or zip code, it will not charge taxes on draft orders. This is problematic when sending customers invoices for products that will not be shipped (will be picked up or delivered). Even if I add the city to the customer's account, it seems to need at least a zip code.
It's very difficult to find out why this might be happening without taking a closer look at the settings in your admin. It could be a multitude of reasons as to why it could be happening. This is something we'd need to access your account in order to resolve. We’re not able to provide account-specific support via the Shopify Community at this time, we’d be happy to continue assisting you through live chat, email, or callback. Please visit our support team here and log in to your account to create a support request.