reg purchase requisition number range

Dear all,

We have a requirement that during MRP run for different purchasing activities like domestic,imports and subcontracting we should get diff document types of purchase requisitions which we have done through

MRP groups, the problem is for different document types in purchase requisitions they have give

different number ranges and as per the document types in P.R it should pick the corresponding number

ranges, although we are getting diff P. R document types but we are not getting number ranges

How to do it, is thereany user exit to do this .

Thanks in advance

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