5) Connecting Instagram again.
This time, we will add your Instagram account from Facebook natively.
1. In the same Instagram menu you were in Step 4), click on Log in.
2. Enter the credentials for the Instagram business account that needs to be associated to this Facebook business page.
3. You will be prompted to Switch to Business. Do so. You may need to put in Contact Information to continue (Email, Phone or Address will work). This contact info will show on Instagram’s Profile Description.
4. Log out of Facebook.com.