Please help - phone not working

[Munty Flumple]

I'm getting nowhere with the Indian call centre. i wonder if anyone here can rescue me.
Brand new install - four days old. I have two phones, one old one on an extention - that's working fine. One new Panasonic digital cordless working on the main socket - when I try to make outgoing calls with that I either get dead tone or engaged tone. Curiously I can call 150 but other than book an engineers appointment for a weeks time they can't help. I'm sure it must be something really simple.

[monkey2468]

Sounds like it hasn't been fully activated on the switch. Have you tried another phone on it just in case?

[Munty Flumple]

I have. Same thing.
Is this something I could do myself? Or do I need to get someone out? Why would I be able to call 150, that's what's puzzling me. When I did phone 150 they told me it was all working OK but it was a struggle to communicate with them to be honest.
Thanks so much for help.