Hello & Welcome to Just Answer,
I'm Greg and will do my best to assist you today.
Sorry to hear of any issue you are having with your phones.
To help you with this issue, may I ask:
1) The FULL Model Number of the phone system you are working with? If this is a cordless system, that model should be printed on a sticker on the bottom or back of the MAIN base.
2) What phone service provider (phone company) you have for this phone line?
3) WHEN did you first notice this issue?
Please REPLY using the box below and the SEND button.
Hi again and thanks for that information.
OK - can you do a quick TEST for me - and place a TEST CALL to that same company that did not see the "1" response?
If so, this time try pressing the * key one time - then press the "1" key - to see if it is recognized.
Please let me know if you can do that TEST - and the results.