Bleeding on the pill

Em

So I’m on the pill and have been for about 2 years. I take my pill at the same time everyday and I don’t miss any pills. I’ve just started having light spotting halfway through my pack. I know it can be normal to have spotting on the pill but my doctor and online research assured me o wouldn’t get spotting being on this type of pill. I’m confused as to what’s going on. Can someone shed some light on what might be happening