Zend certified PHP/Magento developer

ExtensionAttribute does not have accessor method getXYZ in class

currently i’m facing the Problem that an extension attribute wont work as expected.
On our test setup i get the Property has no accessor Error, while my local setup runs fine.

The attribute is configured in the extension_attributes.xml and after a compile all files including the necessary code are generated.

Both setups are using the same version of Magento 2.3.6

The interesting part: when i delete the cache unter var/cache the attribute works on time. After the creation of the cache files it stops working and i get the error again.

Maybe one has an idea that could help me solve my problem.

Thanks in advance