The Bone God's Wrath - Heleen Davies

The clock is ticking as Lynne scrambles to save not only the world from destruction, but also the love of her life who lies trapped in a cursed slumber.
In a desperate quest, Lynne must locate the key to the Olymp hidden on Earth by no one else than Rio himself. With the aid of her loyal best friends and the Loop gang, Lynne deciphers cryptic clues that lead her to the Olympian Gods amid a Deadwalker apocalypse.
Just when victory seems within reach, Lynne is suddenly thrust a thousand years into the past, where she discovers that nothing is as it seemed. Forced to confront her past self, she must find a way to break free of the time travel. She has to right the wrongs that have been done before she is trapped in a never-ending loop while a long-dormant evil threatens to destroy all realms.
The stakes have never been higher for Lynne as she races against time to save everything she holds dear.