Thanks for your reply. The SD ROM is a tool for you to recover the phone by yourself, in this way, you don't have to come to service center. And if you are not clear about the process, you could come to our service center as well.
Remember to bring proof of purchase, such as warranty card, receipt or invoice from Lazada, and then visit service center in your city.
If you have any further concern about the repair, you could make a phone call to service center in advance. Thank you.