If when trying to synchronize your device, its indicator LED is flashing quickly but you can't sync, the problem may be that the network you are trying to connect to is a 5GHz network.
First, check the network to which you have connected your smartphone or tablet, it must be a 2.4GHz network.
Keep in mind that our devices can only be connected to 2.4GHz networks, therefore when synchronizing connect your smartphone or tablet to a 2.4GHz network and link the product.
If you don't know how to check it, you can access this article in which we explain how to deactivate your 5GHz network during synchronization.
Once the synchronization is done, you can reactivate the 5GHz network by following your operator's manual and continue browsing the 5GHz network with your phone, controlling the device without problems.
If you prefer not to modify your router settings, you have this article available in which we explain two alternative ways of synchronization.