SIM problem

[Basit55]

In My Samsung A50 mobile

Zong SIM is not working and other SIM is working 

When it put it the zong sim in my mobile

Here showing (MM phone sim is not allowed) 

Please solve my problems what should I do 

[AliRazaShafi]

have you used that (zong) sim in another phone to confirm if sim was working? if it doesn't work in another phone you should get a new sim.

[Rameez_-_]

its ur sim problem not phone problem...replace your sim

[Basit55]

my sim is working on other phone
only zong sim is not working
in one slot