In Educational CF Round 90, I stumbled upon the following rating changes:

The participant with 2088 rating gets a +46 and becomes a master. But participants with higher ranking and lower rating got a much less positive change.

What might be the reason for this error? If this is a one-off error then its fine. But if these errors have occurred in more than one contest or more than once in the same contest, then this should be certainly fixed.