Splunk query for ignoring results with a regex pattern

[malanirishi]

Problem: I want to ignore all results from search that have message: <4 digits> in them. For example: { timestamp: 2021-05-17T22:30:06.299Z, level: error, message: 9173 }

Research done: I have looked into Splunk docs I tried implementing NOT regex "message: \d{4}" and "NOT rex "message: \d{4}" but it did not work.

[ITWhisperer]

| makeresults
| eval _raw="{ timestamp: 2021-05-17T22:30:06.299Z, level: error, message: 9173 }
{ timestamp: 2021-05-17T22:30:06.299Z, level: error, message: 917 }
{ timestamp: 2021-05-17T22:30:06.299Z, level: error, message: 91733 }"
| multikv noheader=t
| fields _raw
| regex _raw!="message: \d{4}[^\d]"