[PLUG] Unable to set 'RequestHeader unset Expect early' in apache 2.4

[Amey Abhyankar]

Hello,

I want to set respective 'RequestHEader' for = Apache not handling
HTTP 100-continue from client HTTP 417

I tried to do some R&D i.e. adding following option at multiple places
inside /etc/aapche2 but not helping =

<IfModule mod_headers.c>
RequestHeader unset Expect early
</IfModule>

Any hints? Thanks.
I am running Apache 2.4.10 in Debian 8.11

Regards,
Amey.