請幫我修改以下英文，MANY TKS

I quited my last job not because of my inability but due to personal reasons. And i thought it was the best timing for me to make a change.
My past working experiences unable me to handle different tasks as a clerk.And I am really confident about the job.Thank you.

我改左d,hope it helps.最尾o既'this is the end of my introduction'可以唔要,講'thank you' would be fine.:)

I decided to quit my last job because I felt it was the time for me to make a change. I took up a lot of responsibilities in my last position and I have learned a lot from it. Now, I am confident and very experience in handling clerical tasks. I am ready and looking forward to more opportunities and challenges.

我覺得自我介紹的時候要表現得好positive, 儘量避免用負面的字眼, 怕會比人覺得你"越描越黑".. 多表現自信的一面會對你有很大的幫助!!

hope it helps! =)