Both are correct and can be understood by English speaking people. It really just depends on the point you are trying to make. For example: if we compare these sentences in the the present form "She cannot see him because she is not wearing her glasses" and "She cannot see him because she does not wear her glasses" The first sounds like the girl usually wears glasses, but today she forgot to wear them. The second sounds like the girl purposefully did not wear her glasses. I hope you understand, and good luck with your studies in English!

She didn't wear her glasses.