Hi Charlie_17,
Thanks for reaching out to us here. Making changes to your sales tax payments and refunds in QuickBooks Online, can have a negative impact on other areas of your books. The best course of action for this situation, is to speak with an accounting professional. If you don't have an accountant, we can help you find a ProAdvisor in your local area.
QuickBooks Online handles these kinds of transactions directly through the sales tax module, to ensure accurate calculations. Here's a helpful guide for your reference, to assist you with recording sales tax payments in QuickBooks Online.
Feel free to touch base with us again, if you have other questions. WE would be happy to help!