https://stackoverflow.com/questions/63338991/how-to-solve-laravel-sslcommerze-integration-error

go to
config/sslcommerz.php

add the project path

'success_url' => 'projectName/success',

Ex: $path = "/eCom";
'success_url' => $path.'/success',

https://github.com/sslcommerz/SSLCommerz-Laravel/issues/38