Count Error // PDF Builder Pro

Dear Sir or Madame,

could you please help me with this error? :/

Ohhhh i found something, the invoice generation seems to be failing due this problem:
Error Message count(): Parameter must be an array or an object that implements Countable
Error Number 2
Error File /opt/RZphp73/includes/File.php
Error Line 381
Error Context {“locks”:null,”filePointers”:null,”i”:0}
Error Detail file:/opt/RZphp73/includes/File.php
line:381
function:CatchShutdownHandler
class:RednaoWooCommercePDFInvoiceAjax
object:[object Object]
type:->
args:2,count(): Parameter must be an array or an object that implements Countable,/opt/RZphp73/includes/File.php,381,[object Object]

file:/opt/RZphp73/includes/File.php
line:102
function:closeAll
class:File
type:::
args:

file:/opt/RZphp73/includes/PEAR.php
line:831
function:_File
class:File
type:::
args:

function:_PEAR_call_destructors
args:

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