Works but not perfect - Devil Dog Concepts Hard Charger Tactical Handle

So I purchased this after viewing several you tube videos. I never heard anyone mention the issue that I have I countered, so this may me a unique problem. I purchased the HCR at the advice of DDC. As I requested a product that would work on a PSA KS47 . The product arrived from optics planet very quickly and priced very well. I installed it without issue. When I pulled back, I immediately had a problem with the handle binding up. I tried repeatedly to rack it,but it kept handing up. I quickly realized that the finish was coming off the right side of the handle as I smelled a metallic Odor. I figured it needed lube, so I used ALG go juice. It really helped a lot. However, I noticed that if I did not grab the charging grab handle as tight as possible against the receiver the charge handle would lock up. I emailed DDC and asked if they sell a smaller grab button part. So far I can function the system, but I have to use care if not I lock the charge handle up.