关于手机故障投诉信的英语作文

Dear sir/madam

We bought the cellphone from your company several days ago and found that we can not use it because of the malfunction which couses us great inconvient.

Would you please check the cellphone and replace a new one for us or get a refound for this.

I hope you could deal with it as soon as possible. Your prompt reply will be highly appreciated.