Hi ​@Dwardh I am sorry to hear about this inconvenience, please try the below steps to do a network reset and let us know if this improves your experience.

For iPhone:

"Go to Settings.
Tap Phone.
Tap My Number.
Use the delete button to remove the old number.
Use the keypad to enter the new number.
Tap Save.
1. Go to Settings
2. Messages
3. Turn off iMessage.
4. Go to General
5. Reset
6. Reset Network Settings.
7. Once the iPhone is open.
8. Go to Settings
9. Messages Turn ON iMessage.
10.This will recognize the new sim and have it verified."

For Android:

Open Settings and then tap General management. Tap Reset, and then tap Reset network settings.

~Marquerita

I should add that my phone works perfectly fine everywhere else apart from home where it’s always worked before

And my wife’s phone is the same. Carried out all the resets (lost my WiFi passwords yay). 
 

no difference 

Hi ​@Dwardh ,

Could you please confirm the post code of your area and I will check from my side please.

Thanks,

Isa🎀