********** purchase on account and no help from fnb

********** purchase done on my account online,my card and pin was safe at times.i contacted ***** department and was advised it would take 7 days to provide feedback. After 7 days no call from fnb so i called to query and was told that they cannot trace the company so they cant help me.i then received an email asking me for correspondence about the merchant which i have no clue about.And well done fnb here comes another debit order from ********** company Computech credit.I need fnb to sort this out and i want a refund for both ********** transactions