Sink pivot rod is stuck, appears to be attached to sink stopper
It may have a chunk of hair on it wiggle up and down while pulling out. Be prepared to pull the trap as everything stuck on this shaft will possibly slip down 1 wife , 3 girls , 6 granddaughters and all but one has very long hair , I have to clean drains in my current house all the time I liked my 3 bath house better I did not have to do it so often.