Calls not reaching Telphi: a checklist

Step 1 – Confirm forwarding is active

The fastest way to check is to query the network directly from your phone's dialler.

UK mobiles

Dial the status codes below and press call after each one. You should see a message showing the number forwarding is set to. If it shows "not active" or nothing at all, forwarding is not set.

*#21#   check forward-all (unconditional)
*#61#   check no-answer forwarding
*#67#   check busy forwarding
*#62#   check unreachable forwarding

If any condition you want is not active, go back to the UK setup guide for your network.

Step 2 – Check your ring time

Conditional forwarding fires after your phone rings for a set time with no answer. If that time is too long, the call may be sent to voicemail by the network before the forwarding rule activates.

Aim for 20 seconds (four to five rings).

UK – EE and Vodafone

You can set the ring time in the no-answer forwarding code itself:

**61*07700900123**20#

Replace 20 with your preferred time in seconds: 5, 10, 15, 20, 25, or 30.

UK – O2, Three, giffgaff, Sky Mobile

The ring time is network-controlled (typically 15–20 seconds) and cannot be changed via dial code. If calls are being intercepted too early, contact your network and ask them to extend your no-reply timer.

Step 3 – Check whether voicemail is intercepting first

This is the most common cause of calls not reaching Telphi. Your carrier's voicemail runs on the same conditional forwarding system. If voicemail is set to a shorter ring time than your Telphi forwarding rule, voicemail wins.

How to confirm it

Call your number from another phone and let it ring without answering. Note which voicemail greeting plays – is it your carrier's generic voicemail, or Telphi?

If carrier voicemail answers, the voicemail route is claiming the call before Telphi.

Fix on UK mobile networks

Dial ##61# to remove only the no-answer route to voicemail, then re-set your Telphi no-answer rule:

##61#                    remove voicemail from no-answer route
**61*07700900123**20#    set Telphi on no-answer route

For Vodafone, clear all conditional forwarding first (this removes all voicemail routes), then re-set Telphi:

##004#
**61*07700900123**20#
**67*07700900123#
**62*07700900123#

For Three, you can disable voicemail entirely: dial ##002#, then set your Telphi rules. To re-enable Three voicemail later, text VOICEMAIL ON to 30044.

Step 4 – Check phone settings that block call routing

Several phone-level settings can interfere with call forwarding. Check each one.

Do Not Disturb (DND)

When DND is on, your phone silences calls locally – but the network still tries to ring your number. Forwarding should still work. However, some DND configurations interact with carrier features. If calls go straight to voicemail with no ring, turn DND off and test again.

Aeroplane mode

Your phone must have a signal for conditional forwarding to work. The unreachable rule (**62*) is designed for when you have no signal, but that rule only activates when the network cannot reach your SIM at all – not when you are in aeroplane mode while connected to Wi-Fi calling.

If you are using Wi-Fi calling, test whether forwarding works in this mode. Some networks apply different routing rules to Wi-Fi calls.

Call barring

Some phones have a "call barring" or "call restrictions" setting that blocks outgoing diversions. To check: go to Phone Settings → Supplementary Services → Call Barring (Android) or contact your carrier. If divert barring is on, turn it off.

iPhone-specific

On iOS, call forwarding can also be set at the device level under Settings → Phone → Call Forwarding. If you have a number set here that is different from your Telphi number, it may conflict. Either clear it out or make sure it matches your Telphi number.

Step 5 – Dual-SIM phones

If your phone has two SIMs, call forwarding is set independently per SIM. You may have forwarded the wrong one.

Check which SIM holds your business number, then repeat the dialling steps using that SIM. On Android, you can usually select which SIM to dial from in the phone settings before dialling the forwarding code. On iPhone with Dual SIM, go to Settings → Cellular and check which number is which.

Step 6 – Carrier plan restrictions

Some plans – particularly older PAYG plans and some SIM-only budget plans – do not include call diversion.

Signs this is the issue:

• You dial the forwarding code and get an error tone or "service not available" message.
• Status checks show the code is not active even after dialling correctly.

What to do: contact your carrier and ask whether your plan includes call diversion and, if not, how to add it.

Step 7 – Reset to a clean state and start again

If nothing above has fixed the problem, clear all forwarding rules and re-set from scratch.

UK mobiles

##002#

Wait for confirmation, then re-run the setup steps in the relevant guide.

BT landline

#21#   cancel forward-all
#61#   cancel no-answer
#67#   cancel busy

Then re-run setup.

Still stuck?

If you have worked through every step above and calls still do not reach Telphi, contact support. Include:

• Your network/carrier
• The status check results from Step 1 (screenshot or note what each code showed)
• Whether the problem is "calls go to voicemail", "calls ring out", or "calls reach me instead of Telphi"