When nun sakinah or tanwin meets ب, the nun converts into a hidden meem sound with ghunnah.
مِنْ بَعْدِهِمْ
mim ba'dihim
نْ or tanwin → م sound
خُلِقَ مِنْ بَحْمَةٍ
khuliqa min bahmatin
نْ or tanwin → م sound
سَمِيعٌ بَصِيرٌ
samī'um basīrun
نْ or tanwin → م sound
عَلِيمٌ بِذَاتِ
alīmun bidzāti
نْ or tanwin → م sound