Is this signal issue happening everywhere @priya412 or on a particular place like your home or work etc ?
As a process of elimination can you try your sim card in another phone and if possible another sim card in your phone which can help to rule out your sim card.
Check any mast checkers your network provides.
There is a diagnostic tool in your Samsung Members app you can run.
And you can reset your Network Connection in Settings > General Management > Reset > Reset Network Connection.
A Samsung Service Centre can take a look at the phone too.
If I can be of any further help then please don't hesitate. Take care. 😎
Daily Driver > Samsung Galaxy s²² Ultra 256Gb in Phantom Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "