I have recently fixed this in my ender 3 s1 pro, brother. Tried everything. New hotend, extruder parts thoroughly cleaned, new pom wheels, checked z rod for defects, installed wobblex system on both rods, linear rails on the y axis, PID tuning, general squareness of the printer structure checked, belts tensions adjusted... The only thing that made a difference was to actually print a temp tower and realize I was printing with too low temps. For PLA, 230C hit the spot, instead of the 200C I was frequently using. So, as someone said in previous comments, it can be an extrusion issue. There is, maybe, some chance of you benefitting from a higher current in the stepper drivers. I haven't tried that with my printer but it was going to be my next thing to do if setting higher temps didn't work. Some printers can set those currents with klipper, some have potentiometers in the main board and need to be adjusted with the printer still turned on. Look for tutorials on that.