Its keeps saying failed to sync with device
We assume you are talking about your mobile device not syncing with a KeyMander 2, but you didn't provide any information to help you.
What phone do you have?
What version of operating system is it running?
What version of the K2 App are you running (current version is 1.1.107)
Make sure you have the K2 App and not the K2 Mobile app.
What color are the LEDs on the K2 when the app fails to connect?
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