I would expect Person_FK to have the little three prong line like Asset_FK does. Maybe double check the field definition for Person_FK to make sure it's correct.
Yes. The problem is that you are auto-generating data on the FK side. That data should be pushed in from the PK side. Remove the auto-enter calc on the FK field.
Now I am in person layout, with a person assignment history portal but filemaker is not allowing me to input the asset PK into the ASSET FK field on portal.
And when i go to Related Record I am getting the same wrong result... no matter what record I am on.
I would also recommend (when you get things set up again) to do some simple SQL queries - to help make sure both your 1:M (M:M in total) relationships are working.
If SQL is in your skill set it is quick and easy to do.
If you don't speak SQL, you can drop portals onto the layout, one for each of the related tables and verify the result. That's also quick and easy to do.
What you want, it seems.. that multiple Persons can check multiple Assets.
Therefore you connected a Joint Table Asset_History.. That is correct.
Asset Attachment.. hmm.. very sophisticated to have that in a vertical table.. but modern.. Verticalize the data.. A mere containerfield with repetitions could also be used
Service History. Ok.. A Asset can receive multiple "services" . but a service is always only done on one asset.
Looks all good.. that the crow feet do not display.. that is just a filmmaker bug.. or idionsincrasity.
Your join table ASSET_ASSIGNMENT_HISTORY can contain dateCheckedOut and dateCheckedIn fields to describe that. You can also use the absence of a dateCheckedIn to determine if the item is available.