Not applying them correctly, when applying the links make sure you squeeze each side hard so no water can go in to the links
Hair was not washed with a clarifying shampoo, make sure you wash your hair clarifying shampoo prior to installation
Using too much conditioner at your roots, Do not use conditioner on your roots this will make the links slide when you brush
Brushing and pulling too hard when the hair is wet. If you feel like they are sliding when you brush on we hair, you will need to let your hair dry a little before you brush. When hair is wet it reduces it’s volume and this may cause the links to slide
If you have oily hair you will need to wash your roots with a clarifying shampoo only at the roots and your scalp, rinse and then wash the hair with a sulfate free or any low sodium shampoo for hair extensions. DO NOT USE CLARIFYING SHAMPOO ON THE EXTENSIONS IT WILL DRY THEM OUT.