This is the only rule for writing that can’t be bent. You, unique and individual, offer that proprietary gift, your voice. It may hold similarities, but it is yours alone.
Embrace the voice that is you and that will connect with people. Genuine and true is the key. Don’t try to channel your favorite author. While they may be great, it limits what you can do.
Be working to improve your craft always. Read constantly. But write what only you can. Embrace your voice so others can embrace your writing.