fix field msg error

[hello2t]

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[codecov-io]

Codecov Report

Merging #192 into master will decrease coverage by 0.37%. The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #192      +/-   ##
==========================================
- Coverage   73.09%   72.72%   -0.38%     
==========================================
  Files          36       36              
  Lines        1349     1349              
==========================================
- Hits          986      981       -5     
- Misses        314      318       +4     
- Partials       49       50       +1

Impacted Files	Coverage Δ
logging/zap/payload_interceptors.go	84.61% <100%> (ø)	:arrow_up:
retry/retry.go	73.33% <0%> (-2.78%)	:arrow_down:

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