Here are some steps that might help:
1. Appeal the Suspension
Go to Facebook’s Support Inbox or Help Center and look for any notifications about why your page/group was suspended. There’s usually an option to appeal the decision. Provide as much detail as possible, highlighting your ad spend and the good standing of your other pages.
2. Check Violations
Sometimes, even minor or automated mistakes can trigger flags. Make sure no admins or users of your page/group posted something that could violate Facebook’s guidelines. Review past posts and group activity closely.
3. Reach Out to Facebook Business Support
Since you're spending a considerable amount ($4,000–$5,000 monthly), you might have access to Facebook’s Business Support. Open a case through Facebook Business Help and request clarity on the issue. They tend to respond faster to businesses with active ad spending.
4. Wait and Manage Expectations
If Facebook has locked your account for 28 days, it might be tough to resolve quickly. However, continuing to appeal or reaching out through multiple channels (Business Support, Ads Manager) may help speed things up.
5. Prevent Future Issues
Once the suspension is lifted, make sure to audit the content, admins, and activity across your pages and groups. Even small things can sometimes trigger an account review, especially in groups where user-generated content is involved.
I hope these steps help, and hopefully, you'll get your posting rights back sooner!