I’ve done all this too. I have an Easter collection, and added items manually. However, when I go to check it all out via online, only one item shows.
Everything is set as active (my full shop is still under password), i have deleted the products and re added them, I have also deleted the collection and re added it too. Why are they not showing???
I appreciate the context that you have shared with us as that is very helpful!
Since I cannot authenticate you for the store over the Community forums due to the sensitive information that needs to be shared, I am unable to look into the manual collection.
In this case, it would be best to reach out to our live support by logging into your online store using the Contact Us page. This will allow us to securely verify you as the store owner.
Once you successfully login - you will be directed to our Help Center. Select the topic that you would like assistance with to locate the options to Get Support and speak directly with a Support Advisor about the collection.