Hey Natalie! Unfortunately, they don't do walk-in appointments (I've tried). I eventually got one after a week of trying obsessively (50 times per day😑). Apparently, other people have got one at midnight when they post appointments. Good luck.
Try a visa in another country of the European Union. Italy, for example, it should serve you for the entire Union. Query. If you have US nationality, you do not need a visa for 90 days in Spain, you can manage a longer stay.
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