Bounce Car Seat

I bought a car seat sit for my baby boy, the brand is @bounce at mall of Africa. I was specific about the age, I wanted a car seat that would accommodate him until the age of five. By 8 months we couldn’t fasten the belts as they were already small. We tried watching YouTube videos to adjust and we couldn’t find anything helpful. Am not happy with the brand as it didn’t meet my expectations. I still have the box and I need help cause I still need a car seat for my 18 months old baby.