What if my score doesn't match the other scorer's?

Stop and sort it out before entering more balls. Go back over by over, comparing the bowler's figures and the progressive total, until you find where you differ. Most mistakes are a missed wide or no-ball, byes credited to the batter, or runs given to the wrong batter.

If you can't agree, ask the umpire at the next break: they'll remember any extras they signalled. Fixing it at the end of an over is far easier than at the end of the innings.