How to Process Form Request

Rename your form fields so they don’t clash with WordPress query vars, specifically name.

Reserved $_GET and $_POST terms in WordPress:

attachment
attachment_id
author
author_name
calendar
cat
category
category__and
category__in
category__not_in
category_name
comments_per_page
comments_popup
customize_messenger_channel
customized
cpage
day
debug
error
exact
feed
hour
link_category
m
minute
monthnum
more
name
nav_menu
nonce
nopaging
offset
order
orderby
p
page
page_id
paged
pagename
pb
perm
post
post__in
post__not_in
post_format
post_mime_type
post_status
post_tag
post_type
posts
posts_per_archive_page
posts_per_page
preview
robots
s
search
second
sentence
showposts
static
subpost
subpost_id
tag
tag__and
tag__in
tag__not_in
tag_id
tag_slug__and
tag_slug__in
taxonomy
tb
term
theme
type
w
withcomments
withoutcomments
year

Source: http://codex.wordpress.org/Function_Reference/register_taxonomy#Reserved_Terms