I recently moved into this home and I am guessing its a Delta faucet. I am unable to turn the shower faucet enough to get hot water in the shower. I removed the tap handle to see if I can adjust something to have the valve turn all the way so I can get hot water. I can see there is instruction on the white knob(attached picture), "Pull and turn" - I did pull and turn but I could not turn it all the way. Can I get some advice on what I am missing? How can I rotate the knob all the way to get hot water? Any advice would be appreciated.