Hi @lfedele,
If your feed isn’t caching, you may need to clear you host cache. We have seen this before, although it is not very common.
Also, you can set the cache time by going to Feed Them > Settings > Global Options and you can set a custom time if you prefer. Just remember that Instagram has rate limits that restrict how many calls can be made per hour. Once we have exceeded these calls, it usually takes an hour, or a few hours (or even 24 hours sometimes) to have our calls restored.
If this is the case, you may need to wait a day or two to do more accurate tests (which could also explain your caching issue).