Receiving calls to wrong number

[Peter.D]

We have been receiving calls to our landline over the past couple of days not intended for us.  On phoning the home number from my mobile, I get through to a complete stranger.   It appears that the number has been changed without our knowledge.

[Daniel0210]

@Peter.D 

If you dial 17070 from your landline there should be an automated message which includes your landline number. Have you recently moved to Sky Broadband/Talk or changed your package or moved address? 

[Peter.D]

No, we've been at the current address with Sky for 9 years so it's not a new customer situation.

[Daniel0210]

@Peter.D 

So when you dial 17070 is the number mentioned the number you're expecting?