Julie here from Shopify Support.
You can uninstall an app by heading into the Apps section of your admin and selecting the trashcan icon next to it. Once you uninstall an app, you will no longer receive any further charges. What happens when you try uninstalling it? Are you receiving any error messages?
As for the refund, third-party apps are billed by the developers themselves, so you will need to reach out to them directly to request a refund. We have information on how to get help with third-party apps that offers some suggestions on how to get in touch; typically, you can find contact information for developers directly within the app itself, or under the Support section of their app listing in the Shopify App Store.
That being said, it looks like the Batch app is no longer available in the App Store. In this case, our Billing team may be able to assist and it sounds like you've already reached out to them. When you reached out, you should have received a followup email. I suggest responding to that email directly, as it will go straight into the inbox of the team who is handling this matter.
Alternatively, you can contact our Support team through live chat. Since they will be able to authenticate your account and view your billing history, they will be the best to assist. They'll also be able to offer an update on your interaction from a couple months ago.
As a side note, while I appreciate you sharing your screenshot, I just wanted to let you know that I've removed it in order to protect your personal information.
I hope this helps, but please let me know if you have any further questions!