Nokia — Nokia6.1 plus Charging issue

My nokia 6.1 plus was not getting charged even though i was using the charger provided by the company with in 6 months of purchase since i have warranty i went to a nearest nokia care and asked for the reason they said there is moisture in the charging port and said the port need to b changed they charged around 2000 rupees it got fine and again after 4 months same issue started when i searched internet about this issue i got to know that almost every one who owns this phone has faced this issue since i can't afford the charges of nokia care i got the phone repaired in local center for 700 and after 7 months i am facing the issue again. From this I got to know that when I first visited the nokia care the they just told me that reason to gain money even I though I have warranty.