How to get response from third party url and fetch data in response in magento2

I am trying to get some response from third party url.
I am adding the steps I have performed.

Step 1: click on one link

step 2: once click on link it is redirect to third party url with some xml request.

step 3: after some product selection from third party url it is return back in adobe site.

step 4: add those selected products in magento with selactable values.

I have done above all steps but once I return back to the third party url, I am getting error like.

main.DEBUG: Request validation failed for action
“vendorAddPartsControllerAjaxAddToCartInterceptor”
{“exception”:”[object]
(MagentoFrameworkAppRequestInvalidRequestException(code: 0):
Invalid request received at
/var/www/html/vendor/magento/framework/App/Request/CsrfValidator.php:105)”}