求助帮忙写封英语投诉信

求助帮忙写封英语投诉信
作文（一封投诉信）
投诉信
王华在第一百货商店买了一部SQ200的手机,使用不久后,就不能发短信和照象了,希望第一百货商店可以换一部新手机,或着全额退款.

a few days ago,i bought a SQ200 cell-phone at the first department store,several days later,i found that it couldn't send messages and take photoes which greatly affected my use. so i want to ask the first department store to change it for me with a new one or give back all the money i paid for the phone.

对的，就是这个意思