Shopware 5 to Shopware 6 migration Connection stops with http cancel response code

Hello,

We are planing to migrate our shopware 5.6.2 site to shopware 6.6.7.0 (latest till the date).
For that we followed the official shopware documentation.

Shopware 5 and 6 both are on different server. And both the server meets the shopware compatibilities.

we have added API access key for administration user of shopware 5. Also, API access is enabled.
Shopware 5 site is on different server. But, it has no firewall or CORS restriction that can prevent connection.
But, still when we try connecting using Shopware migration extention, it always stop with http cancel response.
here, I am attaching a screenshot for reference. If anybody have any idea about it, please help us.

Thank you :slight_smile: