Hey
I managed to fix this error for php 8.2 by changing the line
around line 5431 in file public/legacy/include/nusoap/nusoap.php
from
} elseif ($delim == '..') {
$this->debug('in invoke_method, calling class method using call_user_func_array()');
$call_arg = array($class, $method);
} else {
to
} elseif ($delim == '..') {
$this->debug('in invoke_method, calling class method using call_user_func_array()');
$instance = new $class();
$call_arg = array(&$instance, $method);
} else {