There is nothing you need to do or eat. The crown will pass through the gut with no problems at all. Taking a high fibre diet like oats, and fruits and vegetables will help the stomach contents to pass more easily and faster through the gut, taking the crown with them
And please do not try to vomit - it is unlikely that the crown will come out .
I hope this helps.
The food reaches the stomach almost immediately, within seconds after swallowing. And if you swallowed the crown while eating bread and ate pizza afterwards, there are hardly any chances of the crown lodging in the esophagus.
If the crown had lodged in the esophagus you would have had a constant cough. The esophagus muscles would have had some amount of spasms and you would have had difficulty in swallowing.