Julie here from Shopify Support. Thanks so much for reaching out and I'm glad to hear that you've been browsing the Shopify Community! There really are a lot of topics here to explore and learn from.
To address your question around inventory, have you made sure that inventory tracking is enabled for those specific products? With inventory tracking, the inventory should remain at the same quantity as it was when the products were imported, unless you've made sales, in which case it will automatically be adjusted based on the quantities purchased.
If you're already tracking inventory, then it would be helpful to know what kind of edits you are making to these products in your Shopify admin. Is there a specific action you're taking before you notice the inventory reverting to 0?
Alternatively, this issue could be related to either a setting or bug within the MIUTT app. While there should be some help documentation available for you directly within the app, it might be worth reaching out to the developers for assistance; they actually have a contact form you can fill out here. When it comes to third-party apps, it's often best to get in touch with the developers directly as they know the ins and outs of their app and will be able to identify any problems. More information on how to get help with third-party apps can be found here.
I hope this leads you in the right direction. If you do end up contacting the MIUTT developers about this issue, feel free to let me know what they say!