Let me start off by welcoming you to the site!!!
First we need to figure if the rifle is cycling correctly. To do this, you will need to load a single round into the mag, charge/fire the rifle from the single loaded mag, and confirm that the bolt is locking back on the bolt lock open catch with the empty mag.
If the bolt is correctly locking back on the last round, then the rifle is correctly cycling, and the problem lies in the mag.
Since you haven't stated what type of mags you are using, let me put it this way, you want to use USGI 30 or 20 round mags in good working order. Cheap clone mags, weak mag springs, and even dirty mags will cause the problem that you are having, and with new USGI mags selling for as cheap as $12, no need to do rocket science on a bad mag trying to get it back in spec.
As for the picture that you have shown, it does appear that the mag is not fully raising the rim of the round back up against the feed lips, and the bolt is making contact on the forward stroke in the middle of the round instead of behind the rim.
But, please do the single round cycling test listed above so we can isolate the problem to either the rifle or mag alone.