If you search for the name of your school on the Apex site and it's not appearing, FirstGiving can help you get everything squared away.
Most likely, the contact from the School/PTO/PTA needs to log in to their FirstGiving account, agree to the Terms/Conditions and enter their personal Legal Name, Date of Birth, and Home Address.
This must be completed by the direct contact at the school, and NOT by the Apex Rep. If they haven't yet completed the process, you can send them these instructions to complete the process.
If you run into problems with this or just want to double-check anything feel free to contact the FirstGiving HelpDesk team at email@example.com or by phone at 877-365-2949.