Url content after ? partialy lost with using redirect
 

I using advanced tracking from some sponsors,where you can add values like at this url:
sponsor.com/something?value=1 for advanced tracking purposes.

But,for some reason,a certain number of sent clicks loses content after ?,so sponsor tracking system is
recording it just with sponsor.com/something and then i have no idea for certain number of traffic to what campaign it belong.Any idea why is that happening?
I use simple header redirect like this:
header("Location: sponsor.com/something?value=1");

Did you try contacting the sponsor in question?

I did,but i realized same thing happening on other sponsors as well,so culprit is probably on my end.

Bump for tech folks

Are you sure that traffic isn't just bots automatically stripping the "?blahblah" off before following the url? Is the traffic real where it sometimes shows sales with that referrer?

It shows as "no campaign". And there was sales with it,so cant be a bot.