3.5mm jack - only hear sound from the left side

Been happening recently. Most of the time it outputs sound on the left side but for some reason it goes some what normal where the right side outputs little to no sound and the left side outputs normal.

Since it's international europe unlocked and I bought from a retailer (Handtec) outside of Canada. How do I approach this to get this fixed? I am sure the phone is still under warranty as I bought this around June (I think).