IELTS小作文. 恳求英语达人给予修改和指点，Thank you very much！

行文还不错，用词挺地道的。第二段太琐碎了，看得出你试图凑字数。以下是几个小问题：

1. Dear Sir/Madam， - Sir 大写, 最后用逗号
2. I'm - 正式半正式文本最好不要用缩写，用I am更礼貌
3. After arrived - After arriving 或者 after I had arrived
4. must been left somewhere - must have been left somewhere
5. it could not be found 严格说起来这个地方不适用被动语态，不过应该不影响雅思评分。
6. Firstly - 改称First比较好，因为First偏重说明时间顺序，Firstly偏重说明重要性顺序。
7. I might left it - I might had left it 过去完成时
8. the customer service replayed - 你是要说replied吧
9. that they did not find any similar item 不算错，但是过去完成时更好
10. Although I will not able to - Although用错了，这句句子的关系不是转折，应该是递进，可以改称比如as well as.
11. withdraw cash for the bank - from the bank
12. inconveniences which mentioned above - 这个地方语法上应该用that连接，而不是which, 建议省略。
13. I, therefore, request - 和due to 重复了，要去掉一个。
14. it could be done as soon as - 这个地方用被动语态不够客气。
15. regards 也太随便了，至少应该写Best regards，正式书信以Dear Sir开头，应该Yours faithfully结尾。