FlowField CalcFormula - Table Filter


I need some help in the following CalcFormula in Sales Invoice Header table:

Lookup(“Sales Cr.Memo Header”.No. WHERE (Prepayment Order No.=FIELD(Prepayment Order No.),Prepayment Credit Memo=CONST(Yes),CLE No.=FIELD(CLE No.)))

CLE No. is a field in both tables that I created.

I’d like to make a FlowField, and in the CalcFormula I would need an inequality between 2 fields:
CLE No.=FIELD(CLE No.), instead of equality. Something like this:
CLE No.>FIELD(CLE No.). But it is not allowed.

Is there any other possibility to alter the CalcFormula, and get the value I want?

Thanks in advance,