Unable to implement the «Pay with stored card» feature because the «ACHSecure Tokenization service» is not enabled for my merchant account

[dmitrii-fediuk]

The «Project Scope» document says:

Card Capture

• Token Storage Flag
• Pay with stored card: use stored card via API call for returning customers

How to enable the «ACHSecure Tokenization service» for a merchant account? (to get SecureToken in an AlphaHPP response)