Struggles with LG 18000 BTU Air Conditioner

I just bought an LG 18000 BTU air conditioner. After two days, the unit was installed. I soon discovered, however, that a TCL 12000 BTU air conditioner provided a cooler and more efficient cooling. Technicians arrived to inspect the LG unit after you requested service. The output temperature of the unit was measured at 15 degrees, while the TCL unit was measured at 6 degrees. As a result, they replaced the gas and vacuumed the area. Nonetheless, the issue persists. Surprisingly, LG's headquarters claims that the unit is operating normally. Regardless, I've measured the output temperature at 15 degrees even when set to 20 degrees at night. The product is clearly flawed, but LG's service center refuses to acknowledge the problem. With the service report in hand, I intend to file a complaint with Consumer Rights. This experience has made me regret my decision to use LG.