since you have a table type.... you should post an array with objects matching the structure of it... in your postman body.. i only see 1 record... wrap it with [ ] to make it an array... looking for more possible issues...
also make sure your sp works properly first by testing it from the sql console.. you can break this into pieces and then test the whole thing from postman.. to test from the sql console.. create a local temporary table with the same structure as your table type.. then call the stored proc.. once it works.. then you can call it from postman..
also, you want to make sure your data types match...