, select and hold the device you want to block, and from the pop-up menu, select Block.You can prevent devices from creating a Bluetooth connection to your phone.
Select Bluetooth.
Open the Paired devices tab , select and hold the device you want to block, and from the pop-up menu, select Block.
Open the Blocked devices tab 
, select and hold the device you want to remove from the list, and from the pop-up menu, select Delete.
If you reject a pairing request from another device, you are asked if you want to add the device to the list of blocked devices.