Reverse lens using Nissin Di622 mark II? - 1

Reverse lens using Nissin Di622 Mark II? I use Nikon D5000. Just bought Nissin Di622 Mark II speedlight. Before, I used built in flash to shoot macro on reverse lens technique. I just need to set the built in flash to manual mode. Everything OK. But, when I used Di622, the camera detected that the the speedlight was in TTL mode even if I already set the Di622 to manual. When using reverse lens, if the speedlight in TTL mode, the camera unable to shoot. Anyone has experience with reverse lens technique using Nissin Di622 Mark II, please help. My camera is already in manual mode

Why is your camera, which is already in manual mode, still trying to detect anything at all? Perhaps there's a menu item, not the flash menu but the main menu, that controls this. Dig into the menu (or the manual first) to seek it out.

Another point is the use of such a humongous flash gun for macro work. The best would be a ring light but if you can tilt the flash head downwards or use it off-camera then why not?