Too much oil is the problem

Yes, you can fix it. Sticky cast iron is almost always from using too much oil during seasoning. The excess polymerizes into a tacky, gummy layer instead of a hard, smooth one.

Hot water and a stiff brush (or chainmail scrubber) will take off the sticky coating. Don’t be afraid to use a little dish soap—modern soap won’t damage cast iron. If that’s not enough, scrub with coarse salt and a paper towel.

Once the stickiness is gone, dry it thoroughly over heat. Then re-season with a very thin layer of oil—wipe it on, then try to wipe it all off. That film is all you need. Bake upside down at 450–500°F for an hour. Let it cool in the oven.

You might have to do this two or three times if the old seasoning is really rough. But it’ll come back.

And next time: less oil. The pan should look almost dry after you wipe it.