Error on activation kit - please fast


I’m getting this error: JSON ERROR: Syntax error

I didnt do nothing on my website, suddenly today one customer try to activate the product and get this error.
I tested with my computer and also the same error on all my products.

Please fast2020-05-12_18h13_47

Please check your workbooks.json file. It may be corrupt or malformed (use for instance)

Thank you but is seems that the issue was created by woo-commerce last version.