Browser reply "<hostname> didn't not send any data"

When user try to browse the url, it replied “hostname didn’t not send any data”

Anybody faced this before?

User —> A10 —> 3 Physical servers

Hello,

Is this for particular clients? What browser are they using?
Is this for HTTP? HTTPS?

Can you share your configuration?

Have you used axdebug or debug packet to trace the connections of the clients?
Or maybe used another packet capturing tool to trace the connections of the client?
If so, what do you see in these traces?