Dropdown with unknown data

hello everyone, please, i need help with the following.
inside the PLANIFICACIONES table, the ID_RTU data is a dropdown, where I added the following validation

but it is showing me wrong values, to select. For example here, I should show to select only the value 3096, but it shows me 1359.

This value, I don’t know where you get it from … To verify that the query I am using has no errors, I ran a test and added a column virtual with the same query, and this one if it shows me the correct data …

And what is strange to me is that if I select the value from the drop-down list, in the database, I see that the correct value is saved, that is, in this example the id 3026.

Please, could you help me find the mistake I’m making?

Thank you so much