How to get a shiny and perfect finish

Hello,
I’m new to resin.. I’m experimenting with wood and resin pendants. I got the wood and the colour I want and also I’m getting quite good with getting the shape I want.. but one thing is still not good- I’m using sandpapers up to the grid of 3000 and after that I’m switching to micro mesh up to 12000.. after wet sanding I’m taking the micro mesh polish to get my pieces really shiny. After that I’m using the micro mesh glos. i apply it with a modified Oral-B electric tooth brush as i found that my dremel tool+polishing bit is too fast and makes the surface overheat=cloudy.. but I also tried to polish my pieces with a polishing cloth and micro-gloss but I still get the same result: a nice wonderful piece shiny and all but with scratches. How do I avoid these scratches? Do I have to sand it longer on the finer micromesh or do I have to use other tools/ or what is a good sanding technique?