Can't make and receive calls

If the problem is with an AT&T cellphone you will need to call them or go log in online to change that feature, however if it is with a Uniden Cordless Phone (the product this question is linked to) the directions below found in their manual should help:

Uniden Cordless Phone
From the base
1) Press [clock/menu] three times. The base displays the current number of rings (2, 4, 6, or TS for toll saver) and announces the setting.
2) Press [>>/select] or [<</select] until the desired ring time appears.
3) Press [set]. A confirmation tone sounds, and the answering machine announces the new ring time.

From the handset
1) Press the MENU soft key. Select the ANSW. SETUP menu, and then the RING TIME submenu.
2) Move the cursor to select a Ring Time (2 TIMES, 4 TIMES, 6 TIMES or TOLL SAVER).
3) Press the OK soft key. You will hear a confirmation tone.

Hope this is of help

Some how your phone was reset or had the tone turned off. Just follow the below guide and your audio should come back on. I would do a soft reset (turn off the handset, remove the battery then reinsert) before performing the instructions.

Tone settings
To select a ringing tone for voice calls, select Tones >
Ringing tone.
To select a ringing tone for video calls, select Tones > Video
call tone.
To set the ringing type, select Tones > Ringing type. You
can also set the device to sound a ringing tone that is a
combination of the spoken name of the caller and the
selected ringing tone, when someone from your contacts list
calls you. Select Tones > Say caller's name.
To set the volume level of the ringing tone, select Tones >
Ringing volume.
To set the various alert tones, select Tones > Message alert
tone, E-mail alert tone, Calendar alarm tone, or Clock
alarm tone.
To set the device to vibrate when you receive a call, select
Tones > Vibrating alert.
To set the volume level of the device keypad tones, select
Tones > Keypad tones.

I have included a link to download your user manual if needed, it comes as a PDF file so you need to have adobe PDF down loader

http://nds1.nokia.com/phones/files/guides/Nokia_E63-1_UG_en.pdf

Hello jinniq51,

i have some tips on how to do it hope it helps :D

Settings
In this menu, you can adjust various phone
settings. To reset some menu settings to their
default values, select Restore factory set.
Tone settings
Select Menu > Settings > Tone settings and from the available
options:
Ringing tone-To set the tone for incoming calls
Ringing volume-To set the volume level for the ringing and
message alert tones. If you set Ringing volume to be level 2 or
above, your phone rings with the ringing volume ascending
from level 1 to the level you have set when there is an
incoming call.
Vibrating alert-To set the phone to vibrate when you receive a
call or a text message
Message alert tone-To set the tone to sound when you receive
a text message
Warning tones-To set the phone to sound tones, for example,
when the battery is running out of power

Hello Hank,

When you make call use the left and right square key for increasing or decreasing volume.

Step by step information at the link below.
Brother Fax T96
The F/T Mode is used to allow the fax machine and the telephones to share the same telephone line. When a call comes in, the fax machine and all extension telephones on that line will ring according to the number of rings you have set for the Ring Delay.
When the Ring Delay is completed, the fax machine will answer the call and determine if it is a fax call or a telephone (voice) call.
The fax machine can determine this by the signal it is receiving on the telephone line. If someone is sending a fax automatically , the sending fax machine will transmit a fax tone (a series of beeps every 3 seconds).
If your fax machine hears these tones, it will receive the fax.

If the fax machine does not hear any fax tones, it assumes it is a telephone (voice) call and will begin ringing the F/T ring tones (double ring) for the length of time you selected for the F/T Ring Time. These tones will only ring on the fax machine's handset (extension or external phones will not ring). At the end of the F/T ring time the fax machine will go into the receive mode in order to receive a manual fax.
(If the call was a voice call and was not answered, the caller will hear the fax receive tones also).

• If you answer the call before the fax machine(during the ring delay period) and determine it is a fax, you can transfer the fax to the fax machine for receiving.
  
  
• If you answer the call on an "extension" phone and hear a beep every 3 seconds (automatic fax) or silence (manual fax), press *51 or *91 for New Zealand (remote activation code) on the telephone keypad, wait to hear the fax machine turn on (chirping sounds) and then hang up.
  
  
• If you answer on the handset of the fax machine and hear a beep every 3 seconds or silence, press the Fax Start or Start/Copy key on the control panel of the fax machine and then hang up the handset.
  
  
• If you answer a call on an "extension" phone during the F/T Ring Time, you will hear the F/T ring tones.
  To release the call from the fax machine, press #51 or #91 for New Zealand (remote deactivation code) on the telephone keypad and you can speak to the calling party.
  
  
• If you pick up the handset of the fax machine during the F/T ring time, you may talk to the calling party immediately.

Try unplugging all sets and call in. Do you still have a faxlike tone, like from an ALARM system or something else down the street?

Hi it's common issue ( I had it myself). Your solution is here : http://www.htc.com/www/SupportDownloadList.aspx?p_id=140&act=sd&cat=0

Rate me if it helped. Thanks.

Take back the phone and have it exchanged

Change your Cellphone!