Aficio 7200

Ricoh aficio cl7200

This printer was running fine and was running low on black ink for a while and I finally installed an OEM cartridge and since then it's not printing black. I pulled out the charge unit and it's not getting any black toner supplied to it. And it's also showing an alert of "irregular toner".

For the life of me, I can't figure it out, I have cleaned everything, there are no clogs in the tubes feeding toner, when I force feed toner, it does put some puffs into cartridge and that's about it, toner does not reach the charge unit. I pulled back shutter on this charge unit and it doesn't have any toner in it.

All other colors are being supplied fine.

Can anyone please help?