I need an Instagram ads expert

Hello, I ran several ads under my account which were super successful for the first two days bringing me 600 followers, however, they suddenly stopped reaching even though the time had days left over and there were no payment problems. I deleted those ads and ran two new ones which after four hours had a reach of “0”. I have disconnected my Facebook from Instagram as I want them to be separate and have placed two new ads that are “pending approval”. But now nothing is happening and I don’t know what to do. Can you let me know what is wrong with my account and why the reach suddenly hit “0” after 30,000