Hi there.

We're experiencing a strange behavior when adding fields to an existing model.

Say we add the field "field1" to the sale.order model via inheritance.

Then we add the field into the XML view.

We installed the module and It works as expected.

Now we add another field called "field2" with the same steps. Now when we upgrade the module, It throws an error like this: 

Field "field2" does not exist in model "repair.order"

We tried to restart the server, uninstall the module and install
the module again but no luck.

Now we made another odoo fresh installation, we installed the module and It Worked. 

"field1" and "field2" are properly rendered on sale.order view.

We don't understand why new changes are not applying.

Could someone help us with that?

PD: We tried in Odoo14 and Odoo15 but same result on both platforms.

Thank you in advance!