Hi PS10,
We have to create a manual N: N relationship.
First please read this blog on creating N: N relationships manually.
https://carldesouza.com/understanding-intersect-entities-and-nn-relationships-in-dynamics-365/
After we create the N: N relationship, D365 will automatically create an intersecting entity. After connecting the N: N relationship for two records, a record is created for this intersecting entity.
Assuming an N: N relationship is created between entity A and entity B, D365 will automatically create an internal entity C.
If we want to create a B record by clicking the + button in the N: N sub-grid of A, then only C record will be created, not B record. Therefore, the form opened after clicking the + button is the C form, not the B form.
There are A and B lookup fields in the C form. We can click the + button in the B lookup field to create a B record, and then use it to fill the B lookup field in the C form. In this way, we successfully created a B record that has an N: N relationship with the A record.
