Revaluation reversal

As per standard functionality, Revaluation journal is created for all foreign currency journal YTD balances (with zero amount in foreign currency & revalued amount in  functional currency). The YTD balance of an account became zero in Jul. Still every month the account is getting hit with 2 JE s 1) Reversal of previous month revaluation JE & 2)current month Reval JE both for the same amount. Could you please let me know why revaluation JE is created for that account though the YTD is zero for both foreign & functional currency. Thanks, Leela