Serial Number Duplicacy for same material during MFBF

Dear Gurus,

As per above screen shot for mov. type 131 in both documents 20 same serial numbers are used on same date

So how it is possible to used same serial numbers again??

We have check Log in IQ02 so there is no log ( To check for User May be change status manually but not found )

We have check also as per below

First 131 Mov @ 18:59:48 with Document no. 4921392569 then 553 Mov. @ 19:04:44 with Document no. 4921392477

So how it is possible that the second document number range is lower than first document no.???

For Document no: 4921392569 UD is Accepted & Stock posting is of 20 scrap quantity

For Document no: 4921392586 UD is Accepted & Stock posting is of 20 Unrestricted quantity

Please guide for the solution

Thanks & Regards,

Madhukar Poul