I get this all the time, in fact I was recently pulled in the office at work because the other staff said I didn't talk to them enough and I often in a bad mood or not smiling enough. I can't help how I look and the fact I can't make small talk for no reason but people just assume what I'm like without trying to get to know me first. So yea, I get this alot, people not liking me for no reason but I try not to let it bother me, Ive kinda got used to it now over the years so I just get on with my life.