I am using Lumia 620 with Vodafone as carrier. Last week it's display unit got replaced. After that I'm experiencing a problem. I don't know whether it has any relationship with display unit change. Phone's signal strength got very low, sometimes empty. And calls got dropped because of this. I tested the SIM with another phone but can't find any problem with it. Contacted the operator, they replied their network works fine.
Is there anyone experienced same or got any solutions?