The quality is very very bad, when I move in the f...

The quality is very very bad, when I move in the first year to now 8 years already, on second floor the wall is keep open very big, after I fix still the same, outside the wall the birds and bees is keep going in inside in the middle wall , we hear that inside the house everyday , but I don t know how to fix, just don t buy it, too bad the quality!