Problems with Granite Blx

[Lukey]

Hello, I've had my Granite BLX for a while now and it always worked fine, now I recently got myself a 3s LiPo, after running it, I charged it and took it out again on the same day, only now it would go into the Low Voltage Mode as soon as I went full throttle, this now happens with my 2S as well as my 3S, what is the problem here and how can I fix it?

Thanks in advance

-Luke