error 500 creating new back office order

[robertopogliani]

prestashop 1.7.6.5, but I got the same error 500 with version 1.7.6.2

The order process in front office works with no problems.
If I try to create a new order from back office, when I save it I get error 500.
The same error with or without disabling Overrides and non prestashop modules.
Default Currency is Euro.
Anyone have some idea?
The following is the result of the Debug:

[PrestaShopException]

La proprietà Cart->id_currency è vuota.    (Property Cart->id_currency is empty)
at line 1003 in file classes/ObjectModel.php

998.             }
999.
1000.             $message = $this->validateField($field, $this->$field);
1001.             if ($message !== true) {
1002.                 if ($die) {
1003.                     throw new PrestaShopException($message);
1004.                 }
1005.
1006.                 return $error_return ? $message : false;
1007.             }
1008.         }

    ObjectModelCore->validateFields - [line 292 - classes/ObjectModel.php]
    ObjectModelCore->getFields - [line 737 - classes/ObjectModel.php]
    ObjectModelCore->update - [line 295 - classes/Cart.php] - [1 Arguments]
    CartCore->update - [line 330 - modules/shippingaddress/shippingaddress.php]
    ShippingAddress->initializeShippingAddress - [line 186 - modules/shippingaddress/shippingaddress.php]
    ShippingAddress->hookActionGetIDZoneByAddressID - [line 970 - classes/Hook.php] - [1 Arguments]
    HookCore::coreCallHook - [line 355 - classes/Hook.php] - [3 Arguments]

[idnovate.com]

It's an error from module shippingaddress, contact the module developer.

Edited May 26, 2020 by idnovate.com (see edit history)

[robertopogliani]

Hi Idnovate,
thanks for your help, very useful and quick. I deactivated the module shippingaddress.php and now everything is working.

One more question related to the same issue.
Before your answer, I was debugging and put the option AdvancedParameters>Performance>DebugMode>"Disable non PrestaShop modules"=YES
And cleared the cache.
The strange thing is that this non-prestashop module was still Activated. Do you know how can it happen?
Thanks
Roberto

[idnovate.com]

Sorry, not sure how it works...