Trying to book a flight between SBP-SGU which are both destinations served by United. I can find flights on Google Flights which link to United who will ticket them to me (I would assume). Since I'm trying to go next week and the tickets are relatively expensive, I thought I would check the price in miles. I can't find any flights between those cities for miles (or even money) when searching on the UA website for any dates. I also checked SBA just out of curiosity, and still no flights to SGU. Is there a reason for this?