Spanish travellers who have had Covid and have been vaccinated just the once face a problem with entering countries that require double vaccination regardless of any natural immunity from having had the virus. The UK and the USA are two countries with this stipulation.
Health authorities in Spain's regions are realising that the protocol of just one jab if people have had Covid is creating this problem for travel. Andalusia was the first to announce that people in this situation can get a second jab.
The Balearics have followed this lead. From Thursday (November 18), there will be a special form on the IB-Salut website for people who wish to travel and are in this situation. Details will need to be given regarding travel prior to getting an appointment.