6230i calling problem

I have a problem with 6230i. I can send network request let say for checking the credit for my card. It works, but when I try to call any number it always gives me busy signal.

I fullerased it, wrote mcu+ppm+cnt, then pm, and after did ui settings, full factory etc.

Is it hardware problem or something else.

I tried it with other sim card, the problem is not in sim card.


Thanks

Its hardware compliant try reworking the network area
first antenna switch