Hello Keith and welcome to the forum.
Sadly when things go wrong in Spain there seems to be a culture of ‘‘I’ve got your money now so tough’’.
All you can do is go to Square media at Los Alcazares and demand a complaints form. Every business in Spain is obliged to have an official complaints book ('Libro de reclamaciones') available. This is a form which any customer can complete which puts the details of a complaint on record and each is followed up by the authorities. It is a legal obligation for businesses to have this book, and to display a notice - usually in Spanish and English - advising that it is available if required. The form is usually in both languages as well.
Once completed, you keep two copies and the business keeps the third. The business then has 10 days in which to reply to your complaint. If none is forthcoming or the reply is unacceptable, you send or take one copy of the form to the local Consumers Office, usually located at the Town Hall. They will then investigate the matter, a process which obviously businesses do not like very much!
If the business cannot or will not produce the forms for you to complete, that is an offence which should also be reported to the Consumers Office. However, in practice, simply asking for the Complaints Book is often enough to trigger an amazing change of heart on the part of the businesses which take the matter very seriously, as the penalties for a proven case can be high.
You also have the option of going to the Consumers Office anyway (without waiting for the 10 days) and reporting the situation. It will certainly take up an hour or two of a holiday, but the more clients who draw attention to shoddy business practices the better.