Changes on Facebook's New Pages Experience
Major Changes on New Page Experience:
Your Page looks more like a Personal profile, where you need to SWITCH from your Personal Profile to your Page Profile in order to interact as the Page.
You may check a more detailed guide on how you can open your Page profile on the New Page Experience on Facebook's Help center on Frequently Asked Questions for New Pages (FAQ)
Only users with FULL CONTROL has access to connect the Facebook Page and manage the Page with the same access as the Creator of the Page.
When trying to connect a Page to MobileMonkey/InstaChamp, you will still see the Page on the list of pages you can manage, but still unable to see the Page on the list of available Pages to Connect to your Company. You need to verify if you have full control of the Page.
To verify if you have full control of the Page: Switch to the Page Profile, then access Professional Dashboard and select Page Access to check if your Facebook profile is listed to have Page access. A Facebook profile with full control can see other profiles that have access to the Page. Your Facebook profile should be under People with Facebook Access and you can see the Add New option on the upper-right side.
A Facebook profile with full control can give you Facebook access. The Facebook profile who created the Page will automatically have the option to Add New users to have Full control so this is the best person to contact to send you an invite to have Facebook access or let you know other Facebook profiles who can. Here is a direct link to Facebook's Help center on how to Give Facebook Access for Pages in New Pages Experience.
Remind the person who will send you an invite to toggle ON "Allow this person to have full control".
Do not forget to Review and ACCEPT the invite to have full control of the Facebook Page.