Zte T22 User Manual page 144

Problem
Unable to
connect to
the network
Cannot
answer
incoming
calls
You cannot
make
outgoing
calls.
Possible causes
(U)SIM card invalid.
You are not within the
network's service area.
Poor signal.
You have activated the
Call barring feature.
You have activated the
Call barring feature.
You have activated the
Fixed dial numbers
Possible solution
Contact your service
provider.
Check the service area
with your service
provider.
Move to an open
space, or if you are
inside a building, move
closer to a window.
Go to Settings >
Call > Call barring,
and then select
Cancel all call
barring.
Go to Settings >
Call > Call barring,
and then select
Cancel all call
barring.
Go to Settings >
Security > Fixed dial
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