The app failed to install due to the way we authenticate you as the store owner.
Currently, https://[yourstore].myshopify.com/ does NOT redirect to http://[yourstore].com/. That redirect must happen before your store can be approved.
Please go to your Shopify Settings > Domains and change your primary domain to a non-myshopify.com domain.
It's also important to check the box "Redirect all traffic to this domain."
Once that is complete, please follow the steps below:
1) Go to your Sales Channels section in Shopify and uninstall the Wanelo Sales Channel
2) If you have a Wanelo account, go to www.wanelo.com and make sure you are logged out
3) Re-install the Wanelo Sales Channel