This looks authentic to me. Normally we don't authenticate for sellers but it sounds like your situation is different (selling a recent buy that isn't exactly what you thought it would be) . Buying online is hard unless you've already tried on the style and that's not possible with older styles.
Thank you so much!!! The seller says she bought it from Nordstrom, and it does look like a solid bag. I'll take your word for it. Thanks so much!!!!