wen switching back to my old number why can't I make phone calls

Hi ​@Hev1956,

I'm really sorry to hear you're experiencing issues with your calls. Please try the steps below, depending on the type of phone you have:

For Android:

• Open Settings
• Tap General Management
• Tap Reset
• Select Reset network settings

For iPhone:

• Go to Settings
• Tap Phone
• Tap My Number
• Delete the old number
• Enter the new number
• Tap Save

Then follow these steps to refresh iMessage:

• Go to Settings
• Tap Messages
• Turn iMessage OFF
• Go to Settings > General
• Tap Reset
• Choose Reset Network Settings
• Once your iPhone restarts, go back to Settings
• Tap Messages
• Turn iMessage ON again

Your iPhone should now recognise the SIM and verify your number.

Regards,

Gemma M

The iD Mobile Social Media Team