There are a number of potential causes of blurry vision after SMILE, or indeed after any other eye surgery including LASIK, PRK, cataract surgery and so on.
Factors that need to be considered include the characteristics of the blurring, such as whether it fluctuates or is constant, whether the blurring is worse for a particular distance, whether it is worse under certain lighting conditions, whether it is getting better over time, and whether there are any measures that help to reduce the blurring eg eyedrops.
A list of causes of visual blurring would have to include things like under/overcorrection of the spectacle power, dry eyes, treatment/surgical issues or complications, etc.
The best thing to do is to see your doctor for a comprehensive evaluation, which is the only way to determine the likely cause and then to treat the problem as appropriate.
