<prompt> Human: Im rolling over my old Voya 401k to my new Fidelity 401k. I have all the documents ready for this. I just want to know how I should mail this because Im scared that it might just get lost in transit or whatever... Do I just use the post office? Drop it off in a blue box?  <response>: If youre concerned take to post office and send it certified with tracking . Not sure if youre in the US or not. 