Voicemail on landline not working

When someone calls my landline and it goes to voicemail, the outgoing automated voicemail says,” the mobile number you are calling is not available, please try your call again later” it then disconnects without giving the caller the ability to leave a voicemail.  Approximately 20% of the time the caller only hears a fax  machine like sound and then is disconnected.

It is my landline voicemail. I do have my voicemail through you,  I do not have a fax machine. My voicemail used to work and callers used to be able to leave messages.

I have tried going through the 99 menu and creating my own voicemail outgoing message hoping it would override the automated one - it does not.

I have spent almost an hour on your chat line and was transferred to 3 different people. I was promised they would be able to fix it - but that didn’t happen.  Instead the chat was abruptly ended.

I called your 800 number, the man thought he had it fixed but alas he did not.

I have numerous health issues and need to be able to have my medical team leave voicemail messages for me.

PLEASE, PLEASE, PLEASE GET THIS FIXED!!