If the dot/reticle appears blurred or spongy, there are several reasons for this. The most common mistake is to focus on the reticle (point/circle point) when looking through the visor. You can check the correct display of the red/green dot by looking into the distance while looking through the visor. Then the reticle and the visual image, both, become clearer.
The brightness setting of the reticle also influences the display of the red/green point. The visor is often set too bright for the ambient light conditions. You can see this, for example, by the halo effect in the inner tube. Please try reducing the brightness by a few steps and look into the distance again. Your reticle should now appear sharp.
Another option for checking the red/green point is the eye relief to the sight: Take a photo of the reticle by focusing from about 30 centimeters. The reticle image should then be clear.
Sometimes the blurred perception is due to our eyes themselves. You can check this by focusing on the blurred part and then turning the optics clockwise or counterclockwise a few times. If the blurred part rotates, then there is a defect in the optics. If the blurred area does not turn, this could be an indication of astigmatism or other impairments of perception.