Hello everyone !
I have some issues and it's something new for me because before I never used pixel and conversion type of ads, maybe someone could share his experience with this kind of campaigns.
The thing is that I'm trying to promote gaming pin submit offers, and I started with engagement and video views ads (in the mean time I tested also traffic ads), after a week when I reached few hundreds Adds to Cart on my pixel (Add to Cart pixel fires when someone click on the offer) I created conversion campaign with Add to Cart optimization, and results for the first day were decent if it comes to Clicks on the offer but my conversion rate was 1.6% which is really bad.
Clicks on the offer: 241
Conversions: 4
EPC: $0.34
Conversion rate: 1.66%
(My total stats for conversion rate since 2017 in that network is 10.82% for pin submit, since year after year it's getting harder and harder I was expecting at least 5% conversion rate)
So for now, Add to Cart objective campaign bring decent amount of clicks but conversion rate is lower in compare to engagement or video views ads.
I would love to try Purchase objective (pixel fire when someone complete offer) but average lead delay for pin submit in that geo is ~11 minutes, so I guess it's not possible to track it with facebook pixel ?
Best regards !
Same as Matuloo said, I don't a reason that 11 minutes wouldn't track the campaign
Thanks guys, I appreciate your help 
The thing is that advertisers won't place my pixel on their side so the only option to track conversions is to redirect people to your thank-you page or any other page that you own, but redirection will happen after lead fired so after these average ~11 minutes when network will receive confirmation people would be redirected to my thank you page with facebook conversion pixel event.
Unfortunately noone will stay after completing an offer for ~11 minutes, they will just leave, that's why with pin submits offers its not possible.
Maybe there is some other method I don't know about ? 
But maybe can someone share their perspective with conversion ads optimized for Add to Cart (in my case link clicks to the offers), is it normal that you will get decent amonut of clicks but less amount of "sales" that you had before with engagement or video views campaigns (while you was warming up your pixel) ?
Hi Mikrog93,
It is fairly common that ATC campaigns have a low conv rate during the initial stage. It will take some time to optimize and warm up the pixel. I would suggest:
1. have a look at your targeting and customer journey. You will likely to find something to optimize for conv rate. For example, block WIFI connection audience and optimize carriers.
2. Try hard on retargeting campaigns on those ATCs.
3. Try LAL on conversions if you have enough data or exclude LAL on dead ATCs (only after you try all optimization and retargeting)
FaceOnAsia
And perhaps try different similar campaigns/advertisers.... others might have a better conversion rate, before blaming your current funnel/setup!
Add to cart is a not so good pixel event lol, is it possible to set up as leads? Even with the delay it might still work out fine