I have two female guinea pigs a bit older than a year. About three days ago, they started to slowly ignore their pellets and hay. Just today, as I was about to feed them their veggies, I noticed that their pellet bowl was completely full. The hay has been messed around with but it is still fairly full. They were very willing to eat their vegetables and vitamin tablets/ treats but when I tried to give them their pellets, they just turn away. What do I do?