我已经辞职了，今天是最后一天在这上班，很高兴认识你，也很感谢你对我的关心，谢谢！

I have already resigned from my position,today is my last working day,nice to meet you,thank you for your kind attention for me,thanks!

I have already quit,today is my last day for working here, glad to see you and thank you for your kind care to me. thanks a lot!

I've already resigned, and today is my last working day. I am very glad to meet you here and very appreciate your kindly help. Thanks so much!

我已经辞职了，今天是最后一天在这上班，很高兴认识你，也很感谢你对我的关心，谢谢!
I have quit my job already and this is the last day
I work here;it's really nice knowing you and thank you very much for your concerns,a million thanks!

2楼的比较好吧，我认为。。。。。。

我已经辞职了，今天是最后一天在这上班，很高兴认识你，也很感谢你对我的关心，谢谢！
I have resigned, today is my last day to work here, glad to meet you, and thanks for your care. Many thanks indeed.