Raja Lisensi is one of the best landing pages you can find out there. Just a few products with a big call to action and a big big discount. That´s it. There is no much to do here. Either you buy the product, you contact them or you leave. If you want to sell focus on that. Do not try to cover too many areas of your business. Good product, good quality and good pricing.
Also, make WhatsApp your main point of contact. Is fast, easy to use and it is always on for your customers.
Keep selling more and more.