I wouldnot say my accent is perfectly american but its also not that bad.

However when i talk over phone for some official reasons or for getting informations, they usually ask my name and since its quite long and hard to pronounce i have to spell every time. Each time i do it they usually miss or mutate some of the alphabets
when i say my name is : s-y-a-k-u-u-r-i-o-l-a-k-u-n-c-h-l-m-b
they ussually understand it as: s-i-a-a-u-u-r-i-o-l-a-k-u-n-c-h-l-m-p

how can i improve it??