A place to politely discuss the tools, technique and culture of photography.
This is not a good place to simply share cool photos/videos or promote your own work and projects, but rather a place to discuss photography as an art and post things that would be of interest to other photographers.
If it is ONLY the red dots that are blurry, my guess is that someone tried to clean the focussing screen with a swab and buggered it up. That's a €250 repair. So if it's usable, I'd leave well alone.
Source: I was that idiot, I made the same mistake with a Canon 200D.
Sounds like the focusing screen. In Canada if you bring your camera to canon for a sensor cleaning they install a new focusing screen as part of that service and it’s only like $60 or so. You might want to do that.