Sudden loose bowels

My dog is a labradoodle, and is of 2years old, few days back, we noticed that he pooped a little bit on our sofa, while cuddling up with me. And tonight I noticed he pooped again, while sleeping on his bed. I have noticed this twice so far, he never had issues previously. During the day he always has a healthy poop, whereas now I saw loose bowel stuck on his butt, any idea what’s happening to him?