Sick vine

[Adam peri]

We have three vines living in different pots for almost seven years. They never gave fruits, Except one, once. Soon after the leaves appear they get spots where the light goes through and then the leaves wither and die.
After I prune it leaves grow back and soon the same cycle repeats itself

 

[Tetters]

Welcome to the forum @Adam peri
Vines are very prone to mildew. They need lots of air circulation and need thinning out a bit with the secateurs. They also need daily watering and lots of feed. Osmocote is good, a slow release fertiliser. Once your vines have mildew, it will stay in the plant year after year unless it is sorted out with a suitable fungicide - it won`t go away on it`s own.
Although these fast growing hungry plants can be successfully grown in pots, I think they do best in bright breezy areas where they have a bit more space.