Why would there be more than one value in a specific index in the Pandas series

I looked up the 0th value of the series called ‘list’, but two values ​​came out. For example, if I run list[0],

0 20210108000843

0 20191025000489

It comes out like this.

And if I look at the format with type(list[0]), it says Pandas series. (If it has 1 value in 0th index, it appears as str. but in this case it appears as series)

And if I print the list with the print statement, I get 98 values ​​from 0 to 97. However, if I query the length of the list with len(list) with the len statement, 198 more than twice the length are displayed.

Any idea why this is happening?