Hey @Tobias77
Thanks for the info and you have reached the german community here, but we can chat in EN too, no problemo! 
Regarding your problem, there are a few checkpoints first we need to go through, and these are:
- What have you tried so far and what didn’t work?
- What support or developers have you consulted with so far?
- What do the Developers of the custom built ERP-System say, seeing that they are responsible for building their ERP-API?
As of the Gift Card API - you are correct in assuming it is only available to Plus Store currently, as you can see in the link you provided:
The gift card API allows Shopify Plus users to create, update, disable, enable, and retrieve gift cards, which is not available on the lesser plans. To connect your ERP system with Shopify’s API, you’ll first need to authenticate. Typically, Shopify uses OAuth for authentication. You would need to create a custom app in Shopify and get API credentials (API key and API secret). After authenticating, you can exchange data between the systems and Shopify APIs use JSON for data exchange. Here’s a sample API call to create a gift card:
POST /admin/api/2022-04/gift_cards.json
{
"gift_card": {
"note": "This is a note",
"initial_value": 100.0,
"code": "abcdefg"
}
}
You’ll need to write scripts in your ERP system to push the Gift Card Data to Shopify. When a new gift card is created in your ERP, a corresponding API call is made to Shopify to create the same gift card. This can be done using the POST /admin/api/2023-04/gift_cards.json endpoint.
You then regularly call Shopify’s GET /admin/api/2023-04/gift_cards.json endpoint to fetch all gift cards and update your ERP system accordingly. This will ensure that any gift cards created in Shopify are also available in your ERP.
However, as you are unable to access the Gift Card API, you may have to consider alternative approaches, like the following workarounds:
- You could create gift cards in both your ERP and Shopify store manually. This might be feasible if the volume of gift cards isn’t too high.
- If the gift card synchronization is crucial for your business and the volume is high, consider upgrading to the Shopify Plus plan. This will give you direct access to the Gift Card API.
- There might be third-party apps available that could help you with the synchronization process. However, it’s crucial to review such applications for compatibility, security, and reliability.
Please consult with Shopify’s support or a knowledgeable technical expert before finalizing your approach to this issue.
