# Anyone can help me? A Unknown Domain key ERROR Occur in my Timeseries Chart

**URL:** <https://forum.inductiveautomation.com/t/anyone-can-help-me-a-unknown-domain-key-error-occur-in-my-timeseries-chart/44012>\
**Category:** Ignition\
**Created:** [March 3, 2021, 2:19am UTC](https://forum.inductiveautomation.com/t/anyone-can-help-me-a-unknown-domain-key-error-occur-in-my-timeseries-chart/44012 "2021-03-03T02:19:05Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![baisea2018](https://avatars.discourse-cdn.com/v4/letter/b/5daacb/32.png) [@baisea2018](https://forum.inductiveautomation.com/u/baisea2018)\
**Post date:** [March 3, 2021, 2:19am UTC](https://forum.inductiveautomation.com/t/anyone-can-help-me-a-unknown-domain-key-error-occur-in-my-timeseries-chart/44012/1 "2021-03-03T02:19:05Z")

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I am now visualizing my data in the report using Timeseries Chart.  
The domain key I am expecting is the "real\_t\_stamp"as follows:

 ![数据1](https://us1.discourse-cdn.com/inductiveautomation/original/3X/f/9/f97bd3203696fa80f1d1e99aabfac576565f7708.png) ![数据2](https://us1.discourse-cdn.com/inductiveautomation/original/3X/c/5/c5c8b3667ff39bf60464edc608c296ab22f80db0.png)  
However, when I switch to preview tab, the timestamp weirdly became “1970-01-01 08:00” and I have no clue about this issue.  
 ![表](https://us1.discourse-cdn.com/inductiveautomation/original/3X/9/1/91574f161f231fbdc86110f8c5e50270a90c60f6.png)  
It would be high appreciated if any help could be provided!!