請教英文文法

I don't know what "Case" is.
The case was "filed", not "received" if you are talking about a court case.
We would say "the documents" if you are talking about physical files.
If you are talking about physical objects, like a case of beer, you need an article before the noun, i.e., "The case".

Passive voice should be used.

Below are the correct ways to express date and time.

The case was received in the afternoon of Jan 1, 2000.
The case was received at 3 pm, 1st Jan, 2000.
The case was received on 1st Jan 2000.
The case was received this afternoon. (no preposition before this, that, next, last)

Case was received on 1.1.2000 noon. or
Case was received in the afternoon on 1.1.2000

1. case 是不會自己收自己的, 應用被動句
2. 先寫時間, 再寫日期
3. in the afternoon 是標準寫法, 不要隨便更改, 況且 'the' 已有 '這' 的意思