This can occasionally happen when you upload an album that includes singles where the album has a release date later than the singles. The most recent release date per track is what Instagram looks at, so it's likely those previously live singles simply had their release date overwritten by the album release date on Instagram's end.
To get this fixed up, please submit an Instagram Resubmission Request here:
Instagram Resubmissions Form
For future reference, you can avoid this by uploading the album before the singles, or by making a request to "update" the release date for the singles in DistroKid to their original release dates after uploading an album that includes those singles on it.
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