First thing, please Disable then Enable  the Alexa Skill within the Alexa App. 

Have you changed your location in your Sonos profile on www.sonos.com.  Are you using the same email account across the two locations?

Edit:

You may also need to update the Device Location for your Sonos Devices within the Alexa App.

Thanks for your reply!

I had Disabled the Sonos skill from the Alexa app but now I am prevented from re-enabling it as I get this message “You are not elegible to enable this skill due to geographical restrictions.”

I did change the location on Sonos using the same email address. Do you think I should delete my sonos profile and start again?

There’s no benefit in deleting your Sonos Profile.  What is the location of your Amazon echo devices? (Alexa App>Devices>Echo & Alexa> each device]>device location

Please also check: Change your Amazon Account Country - Amazon Customer Service

They are all in Spain.

Note my Sonos speakers that were based on the UK originally are not on the list of devices as I deleted them hoping I could reinstall them. But I have not been able to add them back.
 

Can you check my generic Alexa Issues post: Tips & Tricks - Resolving Most Alexa Issues | Sonos Community

It is solved now!! Finally! Thanks for your help!! 

What worked is removing all devices from Alex Desktop and re-adding. Not too sure what happened but it worked. Thanks for all your support! 

Great news :)