Install libnusoap-php by entering the following commands in the terminal:
sudo apt update sudo apt install libnusoap-php
SOAP toolkit for PHP
NuSOAP is a rewrite of SOAPx4. It is a set of PHP classes - no PHP extensions required - that allow developers to create and consume web services based on SOAP 1.1, WSDL 1.1 and HTTP 1.0/1.1.