Probably you will, Kathy. If two profiles are wrongly merged, the only solution is to recreate one of them.
However, this would be a good opportunity to make sure beforehand that the "Unknown" surname really cannot be determined. It is much better to create a profile with the correct surname first if at all possible than to have to change it later.
After recreating the profile, it would be a good idea to add details to the biography, or a research note, explaining why the two Anns were not the same person. This might help prevent another incorrect merge in future.