Verykool i604 - Manual (Page 68)

Appendix B: Troubleshooting
This section lists some problems that you might meet while using
your phone. If you feel that your phone do not operate normally,
please reset settings first, and then follow Troubleshooting
Guide. If you are still unable to solve problems, please contact
the authorized service center or the store from where you
purchased the phone.
Problems Solutions
Can not
answer or
make a
call Make sure that the phone has been switched on.
Make sure that the battery is charged.
Make sure that the signal intensity is high enough.
Make sure the own number function in the call
setting is system preset or number sending.
Make sure the line switch in call setting is the
system preset line. Check whether you have set
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