Help on GR/IR GL Account Clearing

Hi Experts,

We are having problem with clearing GR/IR Account.

Following is the scenario;

PO -  Item 10 -  MXN 4700 (Amt in LC USD 3500) &

Item 20 -  MXN 2300 (Amt in LC USD 175)

Entries at GR 

Debit GL (Exp)  - MXN 4700 (Amt in LC USD 3500)

Credit  GL 3XX GR/IR - MXN 4700 (Amt in LC USD 3500)

Debit GL 5XX (Exp)  - MXN 2300 (Amt in LC USD 175)

Credit  GL GR/IR - MXN 2300 (Amt in LC USD 175)

MIRO

When we look at MIRO header level there was no change but when look amounting document following entries were generated     Vendor -  Account  MXN 7920 ( USD 580)

Debit GR/IR  3XX A/c  MXN 8000 (USD 590)

     Credit GL 5XX (exp) MXN 3300 ( USD 245)

Debit GR/IR  3XX A/c  MXN 2300

Vat output A/c  MXN 1120

VAT withholding MXN 200

Exchange real account is "0"

The difference in GR/Ir account not able clear.

Credit  GL 3XX GR/IR - MXN 4700 (USD 350)

Debit GR/IR  3XX A/c  MXN 8000 (USD 590)

. We have no idea how this happened. I would like to understand how this occurred as well, so we can avoid this happening again.

Pls note we tried MR11 but document didn’t get picked up.

Any help will be highly appreciated.

Thanks in advance.

Sanjay