Lumia 535 restarts on its own?

I purchased it 2 months ago & it started restarting on it's own while I used to listen to music or when I used to text. I gave it to the service centre who said they repaired it under warranty, just yesterday! Today it restarted AGAIN!

I have an old mirco sd 4gb card in the phone, which has had problems of 'USBC VIRUS' a few times, which corrupted, deleted all data. I have aways used my PC anti virus on it but I strongly think that the memory card has some virus which causes my phone to hang and restart.

Please suggest me what to do?

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