# Support
source: https://developer.mastercard.com/mdes-digital-enablement/documentation/support/index.md

## FAQ {#faq}

Use the [Getting Started](https://developer.mastercard.com/mdes-digital-enablement/documentation/getting-started/index.md) and Good to Know section to learn about integrating with Mastercard APIs and what testing environments are available. Merchants, Payment Service Providers, Digital Activity Customers (DACs), and Gateways can access the Digital Enablement API. Access to each Mastercard environment requires separate encryption keys. In order to effectively manage these keys, a separate API instance has been created for each environment. Yes, a client ID is associated to a particular project. It is possible to use a single Client ID if both Digital Enablement API and Digital Enablement MTF API have been added to the same project. Separate encryption keys are still required for MTF and Production. The sandbox environment will return static responses to correctly formatted requests. Sandbox is a good environment to make sure that you can correctly authenticate with the gateway using OAuth 1.0a and encrypt sensitive data in the requests and decrypt data from the responses.
Note: There is no Sandbox environment in the India region; use the MTF environment. While Mastercard does provide access to the technical specifications and Sandbox API environment in Mastercard Developers, we require customers to follow a formal registration process before production keys will be granted in Mastercard Developers. If you have an existing relationship with Mastercard, please reach out to your Mastercard Account Manager, otherwise please reach out to [Digital.Support@mastercard.com](mailto:Digital.Support@mastercard.com) Merchants implementing Token Connect can use the Tokenize API to obtain additional data elements needed. API Specification specific to the `/tokenize` endpoint can be accessed here: [Tokenize API - Token Connect Specification](https://static.developer.mastercard.com/content/mdes-digital-enablement/swagger/mdes-digital-enablement-tokenize-TCC.yaml) Yes, 3DS authentication can be performed on MDES tokens. In this scenario, the 3DS Accountholder Authentication Value (AAV) must be passed in the Universal Cardholder Authentication Field (UCAF) field and the Digital Secure Remote Payments (DSRP) cryptogram must be passed in DE104. Please refer to AN3363 for more details on DE104. Customers are not required to perform additional consumer authentication during tokenization. However, Merchants/Payment Service Providers are required to continue with the current authentication process as per the Merchant/Payment Service Provider's requirements \& regulatory requirements. Tokenize API will return an error with the reason code: PAN_INELIGIBLE. You should retry after few days and tokenize the card based on issuer availability. For more details please refer to managing tokens section in the use-cases: [MDES for Merchants](https://developer.mastercard.com/mdes-digital-enablement/documentation/use-cases/mdes-for-merchants-use-cases/index.md#managing-tokens)

## Get Help {#get-help}

### Contact us for technical support. {#contact-us-for-technical-support}