There appears to be no information regarding the programming service codes for the Samsung Freeform r350. Hence, you are going to need to need to make other efforts to find out what they are.
- Manual
When you purchased the Samsung Freeform r350, you will have been provided with a manual for the device. The manual contains all the information that you need to work it properly. It should contain all the information that you need in regards to programming service codes.
If you can't find the manual then you may be able to find another one somewhere. You could try looking for one on the Internet. There are many websites out there that offer manuals for free. You may even be able to find the manual as a PDF available for download. You should try looking on the Samsung website, too. Sometimes companies offer the manuals and instructions for their products on a downloadable format on their websites, so don't miss that.
- Forums
Forums could be your savior. If you are not able to find out the information you need from the manual, or you simply can't get hold of one, then computer forums could be the answer. Forums come in a wide variety of categories, and there are many forums out there packed full of people who understand computing and who are very experienced in the field. You may find a computer forum that has members that even own the same device as you and hence, may be able to help with your manual search.
Simply find the forum and then register. Once you have made a certain number of posts you will be able to make your own thread, which means you can ask everyone this same question.