java - Can all html forms be submitted programmatically? -

currently, using selenium api populate , submit fields on form. there servlet in end of form.

this form works follows:

1. when click submit button, form sends post request server, data gets saved current session.
2. then need click save button, , browser send second post request server, , data gets saved.

when tried replicate exact same post requests without selenium, using java, got 200 ok responses both post requests, data did not saved. 200 ok mean data got submitted correctly ? have experience sending data forms, , worked fine me.

this form weird in way 1 has click submit, , browser redirects you, , click save. used live headers, , replicated post , requests word-to-word, , got 200 ok requests. no data saved on server's side. why ? there protection don't know about. please give me hint