You are confusing 2 things.
First you are confusing the Deficit (the amount the government spent minus the amount the government received, in the last year) with the Debt (the total of all the yearly deficits).
Second when politicians say that they have reduced the deficit, you would naturally think that meant that this year the government is spending less than last year. What they mean is that at the beginning of the year, they state the total that they will be spending in the coming year. Then after political pressure, they cut some items from this wish list, and claim that they have reduced the deficit.