usually take longer to display results, often up to 6-9 months. The mistake that people make with a gemstone is, it is often compared to an electric bulb - you click on the switch and it starts glowing instantly. It does not work that way, unfortunately!!
Also do note that real, natural gemstones are costly. You can’t expect to buy a Rs 5000 sapphire from a local jeweler and expect it to show results within days. Hence the earlier point about correct recommendation and good quality is important.