Order wrong once again!

Yet again i visit Mcdonalds and am disappointed with them getting my order messed up.<br> | am allergic to onions and after confirming that i do not want any on my food, they end up putting it on my food.<br> This is not the first time this has happened and its rather irritating because then i am forced to either throw it away or give it to someone else.<br> It is rather frustrating having to drive all the way back there.<br>