Hello,
Is your pump and ac or dc return? I would take it apart and clean it good. (Do not use vinegar since it’s been shown to swell plastic). Once it’s clean make sure your hands are dry and plug it in. What I have found is, if you give the impeller some help it may start and work normal. If it starts then place the cover back on. Some you can not but mine you can. If it works unplug it and put it back together and then again make sure hands are dry and plug it in. (This should be in your kitchen sink), if it works on plug it and try to place back in the sump. If it doesn’t work, then take a small like (paper clip extended and move the impeller), it may make it start. If you have cleaned these with vinegar it’s a good chance the plastic swelled around the impeller and it won’t work correctly.
If it’s a dc pump like mine, it’s a huge benefit to keep the controller somewhere but inside the tank. I hang mine on the wall behind it or on a shelf. The moisture and salt creet just destroys them. Hope this helps, another good idea is to run twin return pumps which I do. It makes it where I don’t have to stress per say, I just have less flow for a short time. I also run twin heaters for the same reason.
Good luck