Printed paper has horrible ink smearing / misprinting for black ink. sometimes random boxes

[jjhughes]

I'm using a 2020 HP OfficeJet 5255 All-in-one printer.

 I'm trying to print stuff but the black ink is printing weird. Some text is printing fine, but most is all blotchy half way through the line of text. See images at bottom of post to see what I mean

It worked perfectly a few weeks ago and I haven't touched it since. The ink cartridges were replaced a few months ago and is still 75% full

-I tried doing an alignment check, but see the image of the page alignment page at the bottom of this post l(see text at bottom of image). I tried to put it in the scanner as instructed, but the printer says it can't detect the page.
- I also tried using the "clean cartridge" function, and when the print quality page that printed after still looked funky I did the "second-level cleaning" option. Didn't help.

- I've tried unplugging the power source of the printer for 30 seconds and then turning it back on
-I've tried taking the cartridges out and followed the instructions in step 13 here to manually clean the area around the ink nozzles
- I've searched this forum for similar issues. I found this post, which seems to be the exact same issue but doesn't have a solution other than contacting support, which it seems you can no longer do.