we are not able to add custom tags in Payment Processor Request Data model

Summary:

We are not able to add custom tags in Payment Processor Request Data model Kindly provide us way to add custom tags in PPR datamodel.

Please find below custom tags details,
1) Custom tag (concatenated Invoice number with some char length in one tag).
2) Custom Tag ( File sequence number ).
3) Custom tag ( Random 16 digit number to be generated).

Content (please ensure you mask any confidential information):

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):