I bought some cheap toner and noticed almost immediately streaking and missing lines. I replaced it with HP toner but now black won't print at all.

Sadly, the following HP support page offers about 8 dirrerent possible solutions, some of which you may have tried. You likely will have to try the others to see if they eliminate the problem.

Myself, I would download the HP Print and Scan Doctor just to see if it worked any magic or offered advice. Alternatively, Here is the support page related to printing issues with this printer: https://support.hp.com/us-en/document/c00599279

https://h30434.www3.hp.com/t5/LaserJet-Printing/A-Vertical-Strip-and-repeated-signs-on-Print-Outs/td-p/5668042

https://www.tonergiant.co.uk/blog/2017/05/black-lines-down-the-page-4-causes-and-how-to-fix/

What causes black lines on paper when printing?
Usually streaks or vertical lines are caused by empty toner cartridge or toner itself is damaged. It's also due to a dirty pick up roller or paper path. You can contact HP Tech Support so they can replace your printer

Hello! Malik Muhammad Mehran Here... your problem solution is that you must replace the cleaning plates in the cartridge...

Remove all of your toners and clean them off. Replace each one and make sure they are well setted in the unit before going to the next one. Make sure the carosel turns smoothly and nothing is hanging up on the sides. Reboot the whole printer and let it settle for 5 mins before printing. toners come lose sometimes when you turn carosel around. Hope this helps you these printers are a ***** to deal with ,but when they are right there great.

Was this happening before you swapped toner?
Is there toner streaks on the drum? Yes? Defective.
What if you stop the printer (open cover) as it passes through the fuser to determine if image is from drum or fuser?
But really....isn't it time to move on anyway???

This should help -

Developer streak
Developer streak is characterized by a line of dark or missing toner
that stretches from the leading edge to the trailing edge. Replace the
toner cartridge corresponding to the color of the developer streak (for
example, if the streak is magenta, replace the magenta toner
cartridge).

Repetitive defects troubleshooting
Repetitive defects are defects that occur in the same vertical position
on the page, but not necessarily on every page. Most repetitive
defects are caused by problems with one of the following, and are
indicated by the positioning of the defect on the page:

developer roller (at 38 mm)

charging roller (at 44 mm)—see additional information under
“Charge roller set” on page 454.

cleaning roller (at 56 mm)

developer DSD wheels (at 65 mm)

transfer roller (at 66 mm)

transfer drum (occurs once per 11-by-17 inch or A3-sized page,
or every other letter- or A4-sized page)

fuser (at 150.5 mm)

imaging drum (at 195 mm)

transfer belt (at 222 mm)

Check the dev unit for missing lines. Also clean the laser glass with the supplied cleaner pad - though if the problem were caused by toner on the lens, there would be gaps in ALL colours.

Check the dev units first. You can also do a stop test whilst a full colour test image is half way through printing and see if the lines are missing off the image on the PCU as well.

you have 2 problem.
1). toner is bad
2). toner is low
change the toner should fix both porblem.
try to clean the roller while you have the toner out. (just in case).

clen your toner surface and check that not leakage.
if leckage then replaCE IT
.
BY

Most of the time when I find this happening on a printer, not just Ricoh's it turns out to be the PCU (photo conductor unit). The color PCU is one unit and the black is a seperate unit. Hope this helps.