Four days is rough, but that's not really a grease trap. It's the drip tray or basket at the bottom. That thing needs a wash with hot soapy water after every few uses, or the old oil and crumbs will absolutely smoke.
Yeah, the "old oil and crumbs" thing is real. I saw a video where a chef said that burnt buildup is what makes your kitchen smell bad and smoke. Cleaning that drip tray often is the only fix.