AP Conversion rate is not coming to FA for MRC enabled book

For our requirement we need to have secondary leger enabled for tax book only difference in secondary  ledger and primary is currency. Let’s say Primary ledger currency is USD and secondary ledger currency is EUR. We have MRC enabled at subledger level for primary ledger  this was done after we created secondary ledger. We are trying to resolve an issue where AP invoice date is not equal to DPIS in this case we want AP invoice conversion rate should be used in place of DPIS conversion rate while doing PMC to tax book, But system is still taking DPIS conversion