Actually, it's
not specific enough to justify a new thread. All of this is apparently related to the same issue - your apparently messed-up iTunes library.
If you want help, make it simple for anyone willing to help to find all the pertinent info. Referring to, "my other thread" doesn't cut it. You cannot assume that everyone reading this thread has also read the other thread. At the least, provide
a link here to that other thread. Even better, post this same info in the other thread, and let the experts from whom you want assistance to decide what is and what is not pertinent info for that thread.
Diagnosis is a tough business. The best thing the "patient" can do is lay it all out there for the diagnostician(s), and let the diagnostician(s) put the pieces together. As soon as the patient starts making decisions about what is and is not pertinent/related and presents only what he/she
believes is pertinent, the patient is cutting him/herself off from a solution.
All that said, I suspect you're seeing this particular error message because you had iTunes Match scan your computer's iTunes library (iTunes > Store > Update iTunes Match). Since the library is messed up (songs missing), of course Match is going to have a problem. The operative words in the error messages are, "not added to iCloud." If it's not in the iTunes library on your computer, it cannot be
added to iCloud. (I could not have figured this out without ALSO having read your other thread.)
In the other thread you were asked to try downloading songs to your computer from iCloud. Did you try to do that? If so, what happened? (Please reply
in the other thread, along with the error message you reported here.)