Amp v4 connecting to BT 5.0 transmiter

Hi, how can I connect Up2stream Amp v4 to Bluetooth 5.0 Audio Transmitter.
It connects automatically to other BT speakers and devices, and I cannot connect it to Amp v4.
I turn BT mode and reset BT by double clicking on mode button on Amp v4, and it does not pair.

I am trying to do that because Amp v4 does not support aptX Low Latency and I have to pair devices with wired devices, so delay would be smaller.

@zpl1025 how can I connect?

The receiver normally just waiting the transmittor to connect, can’t do anything to help connecting.