For successfully connecting your account Instagram requires your Instagram account to be a Professional account (Creator or Business account).
How to check the type of your Instagram account?
If you are using the App version:
Go to your profile page. If you see the “Professional dashboard” tab than you already have a professional account. Skip to the connect Facebook Page item.
If you don’t see the “Professional dashboard” tab, then click on edit profile.
Choose Switch to Professional account option and click Continue to go through the onboarding steps.
You can choose a category that best describes what you do from the options provided and then click Done.
Select account type as Creator or Business account and then click Next.
You have successfully converted your Instagram account to a professional account.
If you are using the Desktop version:
Go to your profile page on Instagram and click on edit profile
Scroll down to the last option on the settings.
If you see Switch to personal account it means you already have a Professional account and you don’t need to do nothing. Skip to the connect Facebook Page item.
If you see Switch to Professional account option, that means your account is a personal type. Choose Switch to Professional account option and choose from Creator or Business account type. Go through the onboarding steps and choose a category that best describes what you do from the options provided and then click Done. You have successfully converted your Instagram account to a professional account.
Pretty simple, don't you think!?