Error importing CSV with data from Rally

[muneet.bakshi]

Import completed with 2 errors:

• Issue can't be created due to the error/s [ '3.45E+11' is an invalid number ]
• Issue can't be created due to the error/s [ '3.45E+11' is an invalid number; A selected user for this field no longer exists. Choose another user. ]

How can I fix this issue? This does not give me enough information to fix the issue. 

[Nic Brough -Adaptavist- · Accepted solution]

You have some large numbers in the CSV that your spreadsheet is taking to be numbers and simplifying their display.  When you save it raw to CSV, then it's saving that display.

Change the columns to be text, which will force the full number to come out, and Jira will be able to read it.

[muneet.bakshi]

Thanks for the response. I was able to get past this error but now I am getting the following error:

Unable to parse datetime: 2020-03-05T20:54:18.877Z using the date format pattern: yyyy-MM-dd'T'HH:mm:ss.SSSZ

Why is the importer unable to parse the date?