"Digital nomad visas are still a relatively new way of legally working in another country for an extended period of time - with the first only having launched around four years ago, in the height of the COVID-19 pandemic which forced many companies to shift to remote working practices."
One of the most common reasons for refusal is failing to show that the relationship is real and ongoing. A marriage certificate or civil partnership registration is required, but on its own, it's not enough.