UK members. . Why are BT so useless ?

The engineer they sent to convert my work landline to VOIP was excellent and very helpful. Charming too.

New BT router, modem for telephony, two new telephones, back-up EE mobile internet in case of downtime, booster between the televisions too.
Programmed all devices to the new WIFI password for me, including laptop and printer.
My old ex-directory landline number was 'ported' to the new equipment.

And I don't think that had anything to do with the length of my skirt that day !

The contract includes all UK calls. International calls are extra..

What I discovered afterwards is that each telephone has a different landline number from my original.
I receive calls on my old number, but when I ring back one of the new numbers shows up at the other end and sometimes people do not recognise it and don't pick up.

I have to say the people I speak to are pleasant but can hardly even resolve the issue I called them about .
When I tell them I can’t access my email , they send a messsge
To the email address I , er can’t access …….🙈🙈

? Bt?

Merely a reflection of British politics -the run on effects of mad cow disease?