Hello @Priyam
The attachments which you are uploading are list of embedded property list attachments or a single/multiple attachments field directly on the work case.
Because, starting from infinity i guess, Link-Attachment record is not created when your attachments are residing in the embedded property list pages of the work case. Hence you will not be able to see them attached to the case.
Even if its an attachment field which contains list of attachments will also work fine. But if its a property on the embedded data class level, then it won’t be saved onto the work case.
There is a similar post on the same requirement you can have a look at,
You can go through and let us know if its the same use case or anything different.
Regards
JC