Floor jack won't release under load, any ideas?

[corvette8n]

I have an old Larin Chinese floor jack that is at least 30 yrs old, pumps up and releases fine when not under load. When I jacked up my truck to change a tire it wouldn't release( I was unable to turn the handle). I even tried to pound the star wheel with a hammer and screwdriver, could not get it to move, I finally had to use another jack to get the load off this one, then I was able to turn the star wheel to release. Is it worth trying to fix?