How to fetch data from a subform to populate a lookup dropdown in other form?

How to fetch data from a subform to populate a lookup dropdown in other form?

Greetings, I hope find you well and safe!

I have a form 1 where user register locations of a property:

Field property in the form (ex. Headquarter) and its locations in the subform (ex. Office, Warehouse, Park, Gas station, etc).

I have a form 2 where user register orders related to locations previous registered on Subform from Form 1.
I would like to provide a lookup dropdown where user finds all locations related with its property in order to register the order to, ex.:

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Form 2 - Service Orders

Field Property (lookup dropdown with all property registered on Form 1 - there is no problem here, because the field show me the form and the field I want to lookup)

Field Location (lookup dropdown with all locations registered to that property in the subform from Form 1) - Here is the point, once the lookup field doesn`t show me the subform with the related fields to set the lookup.

Can someone help?

Thanks in advance.