microSDHC 4GB not working in my mobile phone

I just bought a 4GB microsdhc SanDisc card and my Samsung GT-i6220 mobile phone can recognise it.  It can even format the card but when I try to put any file on it or save some photos or even record a TV program, it just doesn’t work.  Some times the phone has even “re-booted” as if I had turned it off and on again.  The card works well in my computer though.  By the way my phone is working well with its 1GB original card (that is also a SanDisk ). could you please help?