Tried to order over the web and it said "error in ...

Tried to order over the web and it said "error in ordering" so I called and they couldn't explain why their site wouldn't let people order. They took order over the phone, but instead of charging $17.00 web price, they charged $22.25 even though they said they would honor the website price. When I picked it up, they decided to charge their price on their register, of $22.25. I showed him the screenshot and basically he said too bad... Needless to say, I didn't tip and told him to ask his manager for the tip. Pizza is a bit small for the price too.