Thanks for the additional information.
Please check the PK cart- is the chip raised up? Did you forcefully install or remove the PK cart recently? Remove the PK and MK carts from the printer, and look inside the cartridge chambers to visually compare the chip sensors, which are located on the back/top of the cartridge chamber. If the chip wasn't attached flat/flush on the PK cart, and the cart was forced in or out of the printer, this could have caused damage to the chip sensor, which is made of very thin wires, that can be easily bent/damaged. The wires need to be bent in a specific way to have proper connection with the chip contacts.
If the printer's chip sensor looks good (the PK and MK look the same), please check the chips on the PK cart, following the instructions below.
38XX “80ml” refill cart reset chip check:
The plastic base of every 3880 reset chip should have three small plastic tabs around the side that hold it onto the cartridge. If any of these tabs are broken or bent inward, the chip will not stay secured to the cartridge, therefore not have a good connection with the Epson chip underneath, which will cause an error. Also, on the back of every reset chip, there should be three metal pins that stick out and touch the Epson chip- the three pins should be equal length for proper contact with the Epson chip. Please check the plastic base to make sure there are three plastic tabs, and if they are all in place, gently bend them outward slightly to ensure they catch and hold onto the cartridge. Also check to make sure the three metal pins are present and equal length. On the front of the chips, please check the gold contacts to make sure nothing is on the contacts that would interfere with the printer's ability to read it- if you see anything on the gold contacts, gently clean them with either an alcohol pad or pencil eraser. After checking all these things, push the reset chips back onto their corresponding cartridges and make sure they are pushed all the way onto the cart for a good connection with the Epson chip, then reinsert the cartridges into your printer and see how the printer responds.
I hope this helps, please let me know what you see, and if you have questions or there's anything else I can help you with.
Best regards~ Dana