If the effective heel height for your weightlifting shoe isn’t sufficient, you can add an additional heel lift that you insert below the insole of your shoe. It’s recommended to take a heel lift from a material that is hard to compress, so the least amount of force is lost. Look for high density EVA or hard plastics.
Note: If you’re a competitive powerlifter, research the rulebook to find out if this is allowed. For instance, the IPF has a rule about this:
“(d) Loose inner soles that are not part of the manufactured shoe shall be limited to one centimeter
This means you’ll have to limit the height of your heel insert to 1 cm if you’re planning to do competitions.