Your code appears to me to be correct, including the ‘phase’ assignment. Note that the units of ‘phase’ are in radians. Convert them to degrees (if desired) by multiplying them by 180/pi.
I’m not certain what you want, so also consider the unwrap function. Use it on the radian units, and convert to degrees later if necessary.
EDIT — If you want to plot it, the easiest way is to use the subplot function. Your plotting code changes to:
title('Single-Sided Spectrum of y(t)');
I did not test that, but it should work.