shoes not lasting more than 3 months

I bought solomons speedcross 3 from trappers trading, and after three months the sole has been worn away completely. The shoes cost me R1700.00 and it lasted only three months. This is the first time something like this happened to me. I love solomons but this is unacceptable. also trappers took 2 months to come back to me with a answer from solomon(no one told me my shoes were back at trappers). they said its the way i walk but due to the fact that i still wear shoes that are 6 years old(this didnt happen to other shoes), i believe this to be a lie. This is a product i will never recommend again to anyone