variable products discription doesn’t appear

Hi,
I have a problem with your plugin for a long time now. When i activate your plugin the variable products discription is missing. I keep all the plugins updated but the updates didn’t fix the problem.

Here are the logs: https://www.dropbox.com/s/pe578sex2fhc1bj/%CE%9A%CE%B1%CF%84%CE%B1%CE%B3%CF%81%CE%B1%CF%86%CE%AE.JPG?dl=0

Thanking you in advance,

Angelo

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