how to schedule posts

I have a Facebook page linked to an instagram account. I want to create a new instagram account for my business linked to my business Facebook page. How do I operate two different instagram accounts on my phone linked to two different Facebook pages without a conflict? The app is not allowing my two different instagram accounts to link to different Facebook pages. "LATER" the app to schedule posts, insists that in order to schedule posts my instagram account needs to be linked to a Facebook page. so I link it to my business Facebook page, but that's not working because I can't allow my instagram account to be linked to that page because the app insists on linking my business instagram account to my personal Facebook page because I also have a personal instagram account already linked to my personal website. How did social media get this complicated?