SummaryCompaniesBritain's FCA financial regulator reviewed financial ads on MetaRegulator found illegal ads for high-risk investment productsOver half were from advertisers FCA had already flagged to MetaMeta says it fights fraud aggressively on a global levelLONDON/SAN FRANCISCO, March 18 (Reuters) - U.S. tech giant Meta (META.O), opens new tab has repeatedly failed to stop illegal ads for high-risk financial products running on its platforms in Britain, despite committing to block them, accord...