[Resolved]  Sony Ericsson Model No: - U1 Satio — Sony ericsson Model no:- (U1 SATIO) not working properly

I Have purchased Sony Ericsson U1 (Satio) phone on 8th of December 2009 from Shop Alfa 5/6,Dadi House, Irla Society, Vile Parle (w), Mumbai – 400 056 under Bill no:- B / 24 for which I also been Issue cash sales receipt and warranty certificate. I am very sorry to write and make a complaint as my phone has started getting hanged within 20 days from purchase. I personally visited the service centre near to my residence I made a complaint at service centre having address :- 45/1785, Sanghmitra C.H.S., Opp Y.M.C.A, D.N.Nagar Link road, Andheri (West), Mumbai – 400 053
I was informed by the person that the phone is having software problems. He assured me that the handset would be working in good condition but everything has come to me as falls assurance. My handset has various problems and I have no solution for the same. I visited the same service centre on 19th Jan 2010 and was issued work order no: - BE310MT110350. I was handed over the handset on the same day with repairing of fault code: - 28- SW Application problem.
The handset has again failed to work and I am facing following problems.
The phone is getting hanged on alternate basis and at the same time if I am receiving a new sms on the phone I am unable to read the sms since the phone is displaying an error message (Messaging Memory Full: End some running application and try again) in spite of having just 5 sms in my inbox even after checking no running applications on the Phone. Secondly the camera is also not functioning properly at camera mode as when I am clicking a photo from the phone it automatically goes to the menu option.
I am totally dissatisfied with the handset Sony Ericsson U1 (Satio) I have no option but to make a complaint in this regard and expect the reputed company like Sony Ericsson would give me solution of my problems at an early date.