Martin Lewis has urged people in the UK to check their state pension entitlement and their national insurance record - suggesting some could be missing out on thousands of pounds in their pensions.His advice was aimed primarily at Britons aged between 45 and 70 and relates to the state pension that was introduced on 6 April 2016. "This is all about your national insurance years; the state pension that you get is paid out based on the number of qualifying national insurance years you have," the Money Saving Expert explained on his ITV show. The Martin Lewis Money Show, ITV