I don't know what, if anything, you are doing wrong, but instead of trying to figure that out you could try a different approach. The way I add albums (called "Pages") to Portfolio is by doing it the other way round, i.e. instead of sending albums to Portfolio from Lightroom, instead open Portfolio and then import the albums from the cloud into Portfolio. I have used the push method from Lightroom to Portfolio in the past (which did work), but I've just got into the habit now of pulling them directly into Portfolio.
So you could try that method, but first I'd clean up the Portfolio connection in the Lightroom Desktop app...if nothing has yet appeared in Portfolio I'd delete all the "projects" from the Portfolio Connection in Lightroom, then I'd open Portfolio in Edit mode (you can lauch Portfolio in that mode directly from the Creative Cloud app on your desktop).
When that is open, click on "Pages" in the Essentials section of the left-hand panel, then when that panel is open (it should be empty if all the "projects" have been deleted), click on the big "+" button at the bottom of the panel and from the resulting "Add Page" panel click on "Lightroom Album" and proceed to select the album(s) from the resulting list.
Does that work?
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