trail cam problems

[Tikkat1x]

so iv just bought a Bushnell 20MP Prime L20 Tan Low Glow Box Trail Camera, had it up 3-4 days now and have checked it every evening, the other day they were drilling maze so it was picking up the tractor's, sometimes they were 20-30 yards out when it picked them up, but most of the time they were 10 yards out, iv walked out in front of it in a straight line and its not picked me up at all, walked 50 yards and turned back, once picked me up 15 paces out, 4-5 times it didnt pick me up till i was 3-4 paces off it, quite a few false triggers, and one night it triggered 6 times and they were all blank green screens, iv come to the conclusion it an absolute back of bollocks,