alter php website form

Hello there. We have a php calculation form that we recently had created by a custom programmer. Though the form works great we are having an issue with the form being emailed multiple times for the same submission. The programmer doesn't seem to know why?? Also, when the form is received by the email recipient there is no sender in the "from" field (unknown sender). We are looking to have someone versed in php to fix these small issues. Thank you. Regards, The Emphasize Design Team