Translate to English. Thanks!

I am writing to let you know that I decided to take the job offer from another company. Therefore, I cannot be able to come for interview today. I am sorry about any inconvenience that will cause to you.

I am regarded to inform your kind department that I will not come to interview today since I has already been employed.

Since another company just employed me, so I cannot go for
the job interview today, sorry about that.