Maria, thank you for your prompt reply.
The seller is non resident and no longer in Spain, and the deposit was passed to the seller via his lawyer.
A check at the land registry yesterday showed that the house is still in the name of the sellers. Is there no quick way to stop completion of the second sale , as it seems that time is of the essence here.
Your advice is much appreciated, and I hope to be able to tell you that having followed it there has been a successful outcome.
Hopefully soon to be less Disallusioned.