Panasonic HC V720- no sound when external mic is plugged in

[g_knoll]

I have the Panasonic HC V720, which I bought principally to do interviews. However, when I connect a mic to the external input, I get no sound from it. The on=-board mic works fine, all recording is fine but the problem remains no sound with an external mic connected.
I have used two differentmics with the same negative result:
TONOR 3.5mm Lavalier Lapel Mini Microphone Dual Headed Clip-on Mic
Lavalier Lapel Clip-on Microphone TRRS 3.5mm Jack Handsfree Condenser
I have checked the manual settings on the camcorder, where you can set levels, but the meters are flat with the pics attached. By the way, a warning comes up when I plug them in saying that the external mic might be in vision when the camera is on wide angle. This seems irrelevant but I thought I'd mention it
Thanks for any help in advance,
I look forward to hearing from you- and from the camera!

[pippas]

Looks as if you're trying to use 'TRRS' (Tip- Ring- Ring -Sleeve) (phone) type mics, rather than the required 'TRS' (Tip- Ring- Sleeve) (camcorder) style ...

You'll need to use an adaptor like this one: https://www.amazon.co.uk/RØDE-SC3-iPhone-Accessory-Black/dp/B00L6C8PNU/ref=sr_1_1?ie=U...de+sc3+adapter

It's maybe cheaper to go for a mic with the right connector - like this: https://www.amazon.co.uk/Speedlink-SL-8691-SBK-01-Spes-Clip-Microphone/dp/B004YEWC22

[smrpix]

The TRRS plug configuration is designed for phones. You generally need either a TRS (stereo) or TR (mono) plug for most camcorders.

Try pulling the plug part way out and see if you get any signal at all. Since you're dealing with sub-$15 microphones, you're probably best off starting over.