Regarding suggestion for my Instagram account

I am having an Instagram account, in which I follow 283 people only, but yesterday in the morning when I opened up my Instagram account there were around 614 people whom I am following. I didn't know any of these newly followed people, nor I have sent any follow requests to any of these from my own will. After that, I unfollowed all of them and changed my password. Today as well, I have seen 1 person is added to my following list, to whom I haven't sent any follow request from my own will. I have unfollowed that person and changed my password again. Nobody uses my phone other than me, and it stays in my vicinity all the time. What should I do now?