I'm having a similar issue on my new iMac. I was trying to update Mac apps such as Pages etc. It asked me to "accept" them on my account page, which I did (or at least, I clicked the button anyway). It accepted and updated three of them but left out Numbers and Keynote. However, there is no button to "accept" them now and they look as though they have been accepted as far as the account page is concerned. But they won't update and I keep getting the same message asking me to "accept" them.
This, I'm afraid, seems to be a major bug in Mojave right now?
I haven't had this problem on my old mid 2012 MacBookPro running the same version of Mojave????