Most payment systems that connect with a phone line will have fairly simple reasons as to why they might fail.

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Verify the connection

For phone line connected systems, check if you have a dial tone on your other phones or fax machine. If the other phone lines work, make sure nothing is unplugged on the payment terminal or at the wall. If the phone line for your payment system is shared with something else, check to see if there’s a dial tone on the other equipment which shares the line.

If your terminal connects via internet, see Why doesn't my POS work with the Internet in the Internet support section.


Call Waiting

Call waiting relies on a beeping tone during your call to advise you somebody else is on the line. This will interrupt a debit transaction, if a phone line is shared with a payment system. Make sure to disable call waiting on any shared lines as this will interrupt any transactions thathappen while someone tries to call you. Call waiting can be disabled in the phone portal in My Shaw under Privacy ->While on a call. Or call into technical support and request it to be disabled.

Voicemail waiting indicator

The voicemail waiting indicator, which sounds like a stuttering tone when you first pick up the phone line, may cause debit terminals to think the line is in use or broken. If there’s a voicemail, check and delete the messages and try again. If this is the cause, check with your terminal supplier to see if it can be programmed to ignore the voicemail indicator, however, some terminals cannot. Message waiting indicators can also be disabled through the phone portal in My Shaw under Voicemail Settings.

Baud Rate

Have the payment terminal supplier set the terminals to 9600 baud rate. This issue is very rare but if the phone line is clear, there’s no call waiting or voicemail waiting stutter tone and transactions are still failing this may resolve the issue.

Shared lines

Since a phone line can only do one thing at a time, make sure a shared phone line isn’t in use. This shouldn’t apply to a dedicated line but many businesses will have other things sharing the line such as fax machines, phone and alarms. Phone and Fax are usually obvious, but the alarm panels may not be.

Testing direct into the phone terminal

To be sure there’s no issue with a line being tied up by other services or by a building wiring issue, you can bypass everything by following the steps on How to connect a phone directly to the phone terminal.