Custom Calculated Attribute

In version 4.6 I could create a custom calculated attribute as shown in the image, but in version 5.5 I get an error when trying to save the same attribute created in version 4.6.

Any suggestion to solve this problem?

Thanks

https://ibb.co/Tb1Qs9C
https://ibb.co/W2NJz2s

Most likely you typed the name, but didn't click on it in the dropdown.

Exactly, that's what I did. I understand then that in version 5.5 it is no longer possible, because in version 4.6 I did the same thing and had no problems.

thanks

It is definitely possible.