SRAM Apex 1 doesn't upshift
That sounds like a sticky shift cable.

Undo the cable from the derailleur, check the derailleur itself is not sticking. You can do this by getting the rear wheel off the ground, pedaling manually and pushing the derailleur body inwards to change down to lower gears, then letting it come back to higher gears. Be careful to avoid catching your fingers in the chain. 

You could also do a quick check of the hanger alignment: from behind the derailleur sight down the chain. The cage should be parallel with the chainrings. This is difficult to do without the bike in a workstand, but you can get the same view by taking a picture with a phone. 

Pull the shift cable out and wipe it down, you can also introduce a small drop of lube into the housing. 

If that does not fix the issue consider repacking the housing and cable.