Instagram connection in Facebook Business Suite Not Working

I am ripping my hair out. I hope someone can help me, please?

I am looking after our group's Facebook and Instagram pages ( Instagram is a professional page)

When I link the Instagram page to Facebook Business Suite it shows up as linked and then I go to post and Instagram is blanked out and said that my Instagram page needs to be linked.

I have tried everything signing out, disconnecting etc ... can someone help me, please?