Dead Mobile Phone Line

[#1]

I used the mobile line to call my GP this morning but subsequently its just completely dead - no dial tone.

The phone is charged and I can use Apps like WhatsApp to talk to people but I need to report the fault to PlusNet but I have no landline and am too poorly to go out looking for a phone I can use?

I cannot find an email address to report this as a technical fault. PS I did pay my last bill! 

Thanks

[#2]

@SAY194 

Have you switched the phone off for 10 minutes to ensure that the call to the doctor has actually disconnected?

[#3]

@SAY194 

"I used the mobile line to call my GP this morning but subsequently its just completely dead - no dial tone."

I'm confused: no mobile phone that I have ever used had a dial tone - just key in the number / memory preset and press "Send"?