The end of your lifter is probably mushroomed, along with a deceased lobe on your camshaft.

Here's the good news...remove the camshaft (you need a new one anyway) and hold a very strong "reacher" magnet-on-a-stick under the bad lifter. Then push the lifter DOWN out of its bore and CAREFULLY extract it through the cam bore on the magnet.

The worst one I did was the furthest-back lifter on a Chevy 250. That's a long reach, and lots of prayers while guiding the lifter back.