Very bad service

Book my phone in for service twice same problem. Loosing signal, restart phone 8 times a day +-, connect to service network same amount of times. Second time phone book in for same problem after they fix it the 1st time, now Samsung saying that due to fisical damage to phone my warranty is voided, due to simcard reader that is damaged, but I still make calls receive calls so on, they charged me ridiculous amounts more repairs due to a Samsung galaxy S5 mini that has been discontinued due to the problems, and Samsung says sorry we will not fix the phone under the warranty. This is the worst phone I have and Samsung is the worst in services and products and they Samsung service centre is unhelpful and try to bambuzel a person, that have the same problem twice with different reasons for phone problems.