If you are unable to connect your Facebook page with CareCart then the possible reasons can be:
You’re not the Admin of the page.You didn’t give required permissions to CareCart.
Only the page admin can properly connect Facebook page with CareCart. Other roles like advertiser or moderator will not allow you to connect properly. So, please make sure that you are the page admin while connecting the page to CareCart.
Please also allow all required permissions when CareCart asks for the permissions.