Hi @donatoaz!
There was a similar case noted in this Community. What could cause CONTEXTUAL_UNKNOWN_SYMBOL error?. In this case it was an ordering issue of the calculations in the .json file.
With this being an error, I would recommend opening a support case. It is best to have it investigated by the support/engineering teams by looking at the logs. It is possible there is a bug the team needs to fix (or they can at least pinpoint the problem and perhaps suggest a workaround).
Here are the steps to open a support case. If your company has someone who manages your AWS account, you might not have direct access to AWS Support and will need to raise an internal ticket to your IT team or whomever manages your AWS account. They should be able to open an AWS Support case on your behalf.