I have the same issue since yesterday

Hi ​@Alina Semjonova and ​@LadyGAGA,

I am so sorry to hear of the issues regarding your signal. Please could you both try the below steps depending on the type of device 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/current 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