Cannot party/group or summon my second account recruit a friend

I need help from someone who has two accounts on one btag. Both accounts are subbed and in good standing. The accounts have been linked in recruit a friend for almost a year and I have NEVER been able to group with or summon my “friend” on the other account. (and that account can’t even SEE mine in friends list or on recruit a friend list.) If I try to add them manually it says player not found. How do people “play” both their accounts at the same time? and what is the point of recruit a friend (besides the gifts) if you are unable to play together?

I think there a level minimum required to summon. Also if they are low level and do a /who the player might not be listed.

I originally thought that…10 months ago. However the characters on the new account are all between 55-60 and I still can’t.