Hello!
I did my first sweepstakes campaign.
The offer URL rotate through a number of domains.
Most of the domain are alright but at least 1 lead to a malware domain.
It was rejected on Smaato based on this malware domain.
Another sweepstakes campaign had this malware domain error too.
I spotted it when I was testing the offer url.
I was using direct link so there was no landers.
At first I thought of using my own lander as a way to overcome this issue.
But if you read the link below "Sites that redirect to domains containing malware" are not allowed.
I don't want my own lander domain to become malware domain.
I did ask my AM about this issue and the answer I got was the offer was alright.
Is this common for sweepstakes campaign?
Is there a way to run the offer even with malware domain?
https://support.google.com/adwordspo.../1308246?hl=en

While expert users arrives I try to answer 
Is the offer in a country that is not the one where you live? Maybe you get redirected because the offer is in another country and you don't use VPN.
The offer is not from where I live.
I don't think its a redirection issue because I tried the offer URL a few times (with and without VPN) and it was all alright with this offer.
David, you could be right!
I tested another offer and the same thing happen but with much higher occurrence. Few clicks and you get that nice red page or another offer.
When I used VPN, the domain rotation stop, and you go to the offer.
However this behaviour is different from the previous offer.
For this offer, the domain rotation was very obvious when you are not from the target country.
This did not happen when I was doing app install 
It sometimes happens to me, without VPN it is crazy
. Anyway, I suggest you to visit the same offer but with another affiliate network 
On a related note, do you guys know of an automated way to check if your domains are getting flagged by any of the browsers?
Ideally, something equivalent to the way that Uptime Robot or Pingdom can send you an email / text if a server goes down.
Traffic protector
I don't have another affiliate network but I am applying for more now. I am quite new at this so it's not easy getting accepted. 
By the way, I am using
Anyway lesson learned, having backup offers and traffics will be useful.
The primary reason for this is generally geo-redirection by the affiliate network, viz:
Offer = [US] Boom Sweepstakes
US user > affiliate link > cool offer page
CA user > affiliate link > random offer trying to make money of ineligible users
The result is usually that the random offer, which bajillions of people have probably been routed to in the past, is flagged.
Solutions:
1) turn off geo-redirection at your affiliate network. Some networks let you turn this off yourself, or ask. This geo-redirection is a general pain in the ass but it makes networks money and they often don't give a crap about the trouble it causes affiliates.
2) use proper tracking rules to prevent this happening in the first place, viz:
US user > tracking system link > rule detects user as US, Android, etc., says OK > affiliate link > cool offer page
CA user > tracking system link > rule detects user does NOT match US, Android etc., says no way buddy > direct URL of offer page
In the end its up to you to understand these systems and work around them to protect your campaigns and prevent stress/irritations.
Thanks Zeno, I understand!