Bulletin Today | Money & SavingsWhen millions of borrowers were locked into high-interest mortgages that hiked their monthly payments to unaffordable levels, mortgage giant Freddie Mac made it more difficult for them to refinance to lower-interest loans, to avoid cutting into company profits, according to a published report. The tightening of refinancing rules occurred during the deepest years of the recession, when homeowners needed help the most, causing hundreds of thousands of delinquencies and foreclosures, according to economists and former and current Freddie Mac officials …