@EjazL

you are facing multiple issues here and out of the box Approval Map can not do this.

1. The way Acumatica AP bills is designed, you can link each line of the bill to a different PO and each PO can be created by a different user. So who is going to be the POs owner you want to look up?
2. Approval log is Kept in EPApproval table not on the document itself and in addition each document can have multiple Approval Log and platform won’t know who do you mean to consider as the base document approved (in your case the PO) Approver.

with customization (for example adding the PO approver to document itself) and establishing some restrictions (ie each AP bill can have only one PO) you might be able to make this work but not of the box.

Thanks for your response

We just want to know in acumatica ERP, against PO when items receive through receipt  and that time any Variance occurs in the system, the system should be asked for Approval which is the original approval name in of PO.

@EjazL 

let say you have invoice AP1 linked to PO1 and PO2 in line 1 and 2 of the invoice and PO1 is Approved by X1 and X2 and PO2 is approved by Y1, Y2 and Y3

So, platform to whom should route the document and how should know it?

@EjazL I reviewed your requirement and I think this is not possible with current functionality 

The reason is that, when you create an approval map for one entity (in this case Bills and Adjustments), approval conditions are based on the screen where the approval map is setup and conditions can't be compared between two different screens.

It will be worth reviewing below article which  is kind of similar situation (not 100%) 
 

@NuwanTharanga62 @EjazL  honestly this requirement is very different from the link. The major issue is that this inquiry requires reading Approval Chain from the PO(s) for the variances. The variance and possibility of multiple POs in AP invoice are on top of it

I have written a 14,000 line customization on Acumatica’s built-in Approval Map to allow deviate from Standard Map, Skip some Steps or bypass the whole approval process while keeping the full history log. To make this happen I needed to know Approval Map in and out. As I had mentioned earlier it is more complicated than just adding a field.

No string attached but if you really needed customization and don’t have the resources to make it work, you are welcome to directly text me to discuss.

@EjazL  Your partner can help you with a customization if needed also.