First double check that everything is hooked up and plugged in. Espeically the RX crystal. A loose RX crystal can drive you nuts. (been there).

Unplug some of the servos, and range check with just one servo at a time plugged in. It's rare, but possible that a servo is freaking out on you.

Most likely, your RX antenna has a problem. First, try relocating it on the plane. If that tail boom is CF or metal, get the antenna away from it, try running it to the tip of the vertical stab or out along the wing.

If re-doing the orientation didn't help, check the antenna. You might even open the RX case (if it has one) to see if the antenna is still attached. It's possible the antenna is broken, but the break is internal, and not visible. You might be able to feel it if you run your fingernail down the antenna (being careful not to tug on it, or cause any harm).

You didn't cut the antenna, did you? Or bundle up "extra" antenna? In the second picture, your anenna looks shorter than I'd expect.