You may want to consider using either paper towels or cocofiber for his substrate... They really like to burrow in cocofiber. Plus, if this is your first frog, the cocofiber might be better since it is cleaner. That sounds strange, but if you use paper as substrate it needs to be changed very often or bacteria will start to grow in it. It also makes it more difficult for the frog to regulate its own temperature if it can't burrow.

If you don't change the type bedding you use, you should get a separate feeding container so this doesn't happen again.