This is likely because the detachable plug from the controller to the blanket is not fitted correctly or has come loose. Please ensure that the detachable plug is fitted correctly into the socket on the blanket.
If the plug is fitted correctly, then your selected heat setting is either too low (in that case please simply increase the heat setting), or the pre-heat time is too short, and you need to give the heated throw a bit more time to heat up. More time is required depending on the ambient temperature.
Please take into consideration that the heated throw may not feel warm to the touch unless it is wrapped around your body. Areas that are not in contact with the heated throw will stay cool.
Should you need any further assistance, please contact our friendly Customer Care Team!