iPhone lightning mic sometimes not activating

Hi,

I have brought a brand new iPhone 11. Since the day I brought I have noticed that some times when I dial / receive a call earbuds microphones will not activated(recipient will be hear from my phone mic, but I can hear from the lightning headset) . If I re plug the lightning cable it will be ok.

It will occur randomly. It was like when the lightning port got idle for some time, but I do some other works on the phone then again I try it the issue will be occur. If I re plug the lightning cable it will be ok for certain period of time. (If I re plug the cable again and again for several times also it will works fine)

I have restored the entire OS from itunes but still it occurs.

previously I have used an iPhone 6s and I restored the entire backup to this new iPhone (Does it can be an issue for this ? ).

But I have tried several times by restoring the entire phone and start it as a new one. But the problem was still there.