Question about Carson Model sports Saint Princess RC

The connection does not work; battery is charged and plugged in, the transmitter in the boat flashes. The remote control is switched on, the light flashes very quickly for a short time and then lights up permanently. But the model does not respond to the test control. What is wrong? The instructions say that the transmitter and receiver must be switched on, but I assume that this means attaching the battery to the boat, as I can't find a switch. Or is there something wrong?