This appears to actually have been the case, because I've shifted the form slightly and am writing again, finally. More on that at the end. I realized something else, though—I see a lot of writing blogs talk about style and structure, about how to write what sells, and about how to fix problems with the plot, with characters, with description, with mechanics. I see blogs talking about how to get out of writer's block by starting something new, having zombies attack the main character, or about how writer's block doesn't really exist and have you seen their post about fixing plot problems? I don't see many, if any, posts about solving problems by stepping back and asking yourself if the story's being told the right way, if it has the right narrative form or point-of-view. Those sorts of problems probably happen less than the other reasons for block, but that doesn't mean they don't exist.
I'm not going to talk about that process of stepping back. Hopefully you already know how to do that. Nor am I going to talk about point-of-view (POV) shifts, because there are plenty of other people talking about those. So that leaves me to list narrative forms, in the hopes that they'll spark a revelation in at least one blocked writer. This is probably not a complete list. Feel free to add to it.
- traditional narrative - a single narrator in any POV, telling a story; may focus on a character, a group of characters, a society, an age, a civilization…. The possibilities are, as with any of these forms, unlimited.
- reflective narrative - technically falls under "traditional narrative", but enough of a shift that I'm giving it its own bullet; the narrator speaks from a point after the book ends, shedding wisdom and insight on events in their past.
- multiple narrative - any story with two or more narrators, describing events from multiple points of view or telling interweaving/parallel stories; often gives the story a broader scope.
- nonlinear narrative - a story that jumps between different points in time.
- frame story - a story that's given a context for being told—a series of discovered letters, an interview, a person editing a manuscript, etc.; will most likely have two narrators, one with much less prominence than the other.
- epistolary novel/diary - a story told through letters, diary entries, email, etc.; can be told by one or more people.
- script - a story told through dialogue and physical actions, rather than prose.
- visual narrative - a story told through pictures (photos, film, drawings, etc.), rather than or alongside prose.
- verse novel - a story told through poetry, rather than prose.
Of course, these forms can be combined. I'd say graphic novels and comics are a blend of script and visual narrative, for instance. Reflective narratives can easily show up in any of the other forms. Scripts can be frame stories or nonlinear. You don't need to stick to just one, either, if mixing them up works better.
I can't tell you if you're blocked because you've using the wrong narrative form or if you're blocked because of something else. Obviously. You need to step back from the thick of the story and work that out yourself. But don't think, like I did, that the first form you choose is the only form the story can take. Be flexible. Try out other forms, if they strike your interest.
For the record, I'm switching my novel from a dual narrative to a frame story that drops one of the narrators and adds in another as the "framer". It'll require a whole lot more new writing, but I think it'll be a better book for it, in the end. It's so good to have the words flowing again.