The Princess of Time Crystals

Time crystals control the time in Timeland but if they break...

Serefina Gracy's family has been controlling the time crystals since her great great grandma activated them until her mother tried to change the future and disappeared and was never seen again.
Serefina's grandma still has the time crystals but she doesn't let Serefina use them. And she always says that no one can change the future. But...something might happen that could make the change of future possible.