useless bank

i've been taking from pillar to post with FNB and their consultants, i have an issue where money was deducted from my account R3871.51 of which i went to the bank to query and request a reversal back into my account since Saturday, i have asked whom the merchant is and themselves they don't know i spoke to various consultants went through the Tc's and C's but yet still not assisted, i have been using other banks before and if you want to reverse it does not take this long and why can't i get assisted