How many moles of aspartame are present in 4.00mg of aspartame? (3 sig figs) This is a part of my online chemistry homework (mastering chemistry)

I know how to do it but when I enter $\pu{1.36E-5}$ into the program, it says that it's incorrect and that the correct answer does not depend on $\times10$. I'm not sure what it wants from me. The answer should be given in moles with $3$ sig figs.
Try putting in 0.0000136. Remember that zeroes between the decimal point and the last numbers do not contribute to significant figures. Good luck.