Low probability of NoAck occurrence in thread communication

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OTBR connects five thread sub devices for UDP communication (once a minute), which requires sending data and receiving replies from the thread sub devices. If it fails and tries again 9 times, there will be a low probability of sending failure (NoAck) in our testing
I think this unstable situation is normal, and the thread signal also needs to be interfered by other wireless signals

But the following log is my first time seeing it

So, I have two questions:
May I know what caused this log to appear
Is there a plan to improve NoAck that lasts for one minute

Full log:
1333.log

[aaa147147]

I may think this is a problem with the thread device or the stability of the thread network, rather than an issue with OTBR. Is my idea correct?

[aaa147147]

The following are logs from 6 consecutive minutes where not all tests were successful, for reference only.
14070.log
14071.log
14072.log
14073.log
14074.log
14075.log