Here again as a supplement: Unfortunately, this means that your camera is not compatible with the lens. You will have to look for a lens that is designed for full-frame cameras and has the Pentax-K bayonet as the lens mount. You could use APS-C lenses with a proper adapter, but I would advise against it, as you would have to digitally zoom the image, so to speak. I hope I have been able to provide additional clarity.

Good day. According to my research, the Pentax K-1 Mark II camera has a full-frame sensor. Unfortunately, according to the product specifications, this lens is only compatible with APS-C cameras. I hope I could help you.
LG Julian