Are you using VPS IP (no proxy at all)? Those IPs are datacenter IPs and IG really doesn't like them. If you do, you'll have to get mobile or residential proxies. Ideally, it's 1 account on 1 IP (proxy).
Yes, of course, make sure you send as many details as possible:
- Tools you use and screenshots of settings
- Do you use Scraper accounts
- What kind of proxy you use and how many accounts per proxy (if you use any proxies since I really didn't understand from your answer)
- How do you promote Main (Mother) account (tagging it in all posts, link in your bio, mentions... whatever you use for promotion) and how often you do it (if it's in posts or comments)?
Take into consideration that child (slave) accounts can be flagged because of the method you do, even if you do it manually.
Promoting just one, same account is a footprint, IG can detect it, it's a link between your slave (child) accounts, and that could trigger the PV/EV/Password Resets/Blocks/Bans.