Simple servo test code you can try with the serial monitor.
I already tried this earlier today and got no response from the servo or anything displaying in the monitor.
One more thought: have you fallen foul of the notorious "My breadboard has two separate ground lines?"
Big picture of arduino/servo/battery wiring.
Sounds like a power issue still.
I already ran connection tests through everything. It's all connected right and all my wires are good. And my power supply is rated to 15 amps.
So not really sure where this leaves me in terms of what I'm even going to be able to get to work. I still get the initial twitches on upload but then nothing afterwards. I have already tried two servos which is all I currently have a available. I can try different types in another week but until then I'm stuck trying to get the Traxxas 2056 ones I have now to work.