VAT is not deducted (Could not be validated / Not returned)

Hi, I′m having troubles in orders with VAT number. For a few weeks, this kind of orders don′t recognize the correct VAT numbers, so it charges the Taxes. The market has been working fine with VAT numbers for more than a year ago and I didn′t change anything recently.
Here is a screenshot of one of the wrong orders: https://snipboard.io/jXd3xR.jpg

The debug mode show that errors:

[2021-06-17 08:20:32] wc-aelia-eu-vat-assistant.ERROR: An error occurred initialising SOAP client. {"Error message":"wsdl error: Getting https://ec.europa.eu/taxation_customs/vies/checkVatService.wsdl - HTTP ERROR: no proper separation of headers and document"} {"process_id":47417}
[2021-06-17 08:20:32] wc-aelia-eu-vat-assistant.ERROR: VAT Number could not be validated due to errors in the communication with the remote service, or because a VAT number validator for the specified country is not available. {"Errors":["An error occurred initialising SOAP client. Error message: \"wsdl error: Getting https://ec.europa.eu/taxation_customs/vies/checkVatService.wsdl - HTTP ERROR: no proper separation of headers and document\"."]} {"process_id":47417}

Can you help me?
Thanks

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