Steak 'n Shake review: mobile order/food

Hello, I normally do not do this, but thought I should make aware this incident. My boyfriend and I used mobile order through your app for the first time. We both ordered the "4 for 4" item. This happened at the Steak n Shake in Lafayette, IN by Meijer. We waited forever in the drive thru just to get our food and realize he didn't get his cookie that was supposed to come with it and I didn't get my cookie nor my slaw I had ordered. I had also ordered a chocolate shake seperate and I did not get that either. The employee was nice, but went on talking to a few employees inside while they kept asking us what did we have even though the receipt was on the bag! We started to leave and that is when we noticed we didn't have everything. However, we didn't even have time to tell them about our order due to the line being so long and we had a place to be at a certain time. I wanted to address this issue.