The arms are loosening on my new Versace sunglasses. How can I fix them?

I bought new Versace shades yesterday and one of its arm is loosening already. How can I fix it at home coz the shop I bought it from is really far off from my house. It takes an hours drive to reach there.|||Most any sunglass shop should take a look at them for free|||Take them in to any eyeglass store, they have all the right tools, plus you don't want to break them.