different exchange rate of bill of exchange

hi experts ,

could you help me to close the below issue

when received check by f-36 in USD and my local currency is EGP

--- the exchange rate for USD = 7 EGP in Month 10

After that i present the check to bank via FTR03 in month 11

--- the exchange rate for USD = 8 EGP in Month 11

i get error in posting and if i present the check to bank in the same month there is no errors happens .

could you help me to slove the exchange rate different in these cases .