Parallax adjustment setting is right and still blurry= usually a problem with optics=usually "cheaper" optics do not work good past fifty yards....
So then most all optics work good at short ranges,but when power is cranked up they do not have the quality=quality costs money.
For me 10yds to 15yds. up to 7x ,then 25 to 50 yds. 12x then 100yds18 to 24 x..
The point I was trying to make is this,better quality scopes can " see" better with less power,a clearer view makes it easier for you to see .
There are plenty of old known brands of scopes that work better than the newer Chinese made scopes and they are lighter and bought used cost about the same..
All optics have a hierarchy,the nicer the nice the higher the price,this is because there are more steps to takes to get them better,the type of glass and the coatings are but a few.
A cheaper scope can work at shorter distance,but when shooting long range or a higher power x said scope will become blurry.
IN optics the lens coatings are of tremendous importance and cheaper scopes do not have them.
One other point is I like fixed power scopes,they are usually lighter and cost less than the same one in variable power;That is because I have a set distance I use for the fixed power.....no reason you can't use a variable power for the same reason....
Did not mean to blab so much,just some things I have learned for me....