Unable to deactivate a primary PS4

So I put my account on another PS4 a while ago and activated it as the primary PS4 so I could access my library of games,I don't have access to that PS4 anymore & am trying to activate my account as primary on my PS4 that I'm using now,I'm unable to deactivate it via the PlayStation app due to already using that once & it can only be done once every six months (which is stupid) when I press activate on the actual system it comes up with the choice to "change to this PS4" however when I select it it says I can't activate this system as my primary PS4. Can somebody give me a solution please?