UNSTRAPPED!!

I purchased a JBL charge 6 speaker at the Bellville branch on the 15 August. Three weeks ago the carry strap broke. Went into the store and was told that i need to purchase a new strap. JBL is known to be a top - notch product. How can the carry strap not be included in the guarantee and neither was this told to me when i made the purchase. I am not prepared to buy a new strap at the cost of R300. I feel it should be replaced as i don't even have the speaker for 3 months. UNACCEPTABLE