Script onForm Submit trigger not working properly - google-apps-script

Question

I created a google form that will take the latest response and move the selected choice to the other section. So if someone checks out a laptop, once they submit the form the laptop choice will appear in the check in section. When I manually run the script it works perfectly fine but once I add the trigger it works for the first few times then it starts creating multiple triggers for one submission which then creates multiple new checkboxes on the form that all say the same thing. Like for example I'll have three different laptop choices when there should only be one. So I had to take the trigger off and I've looked at other similar questions about this problem but they all involve spreadsheets but mine is purely working with the google form so I'm not sure if those solutions will work for me.
I didn't add all my code since part of it is the same thing just with different variables for moving choices from check in to checkout.
var form = FormApp.openById('1I5uMesHbeVZ_RSP8wxmmpPA7-Sgcc4b6dzzH305c8K8');
/**
Responds to a form submission event when the on formSubmit trigger is
enabled
*
* #param {Event} e The event parameter created by a form submission
*/
//function that gets checkout responses
function myFunction(e) {
//getting form responses
var formResponses = form.getResponses();
//getting latest response
var latestFR = formResponses[form.getResponses().length-1];
//getting the item/question responses, checkout check in
var itemResponses = latestFR.getItemResponses();
//looping through item responses to see which item has a response
for (var i=0; i<itemResponses.length; i++) {
switch (itemResponses[i].getItem().getTitle()) {
//if only response to checkout
case "Checkout":
var outAnswer = itemResponses[i].getResponse();
outAnswer.forEach(addOut);
outAnswer.forEach(deleteOut);
break;
//if only response to check in
case "Check In":
var inAnswer = itemResponses[i].getResponse();
inAnswer.forEach(addToCheckOut);
inAnswer.forEach(deleteIn);
break;
//if response to both check out/in
case "Checkout" && "Check In":
var outAnswer = itemResponses[i].getResponse();
var inAnswer = itemResponses[i].getResponse();
outAnswer.forEach(addOut);
outAnswer.forEach(deleteOut);
inAnswer.forEach(addToCheckOut);
inAnswer.forEach(deleteIn);
break;
}}
//getting email response to send email
var email = itemResponses[0].getResponse();
//testing to see if it gets the latest submission
//delete my email later
var subject = 'Response';
var emailTo = [email];
var body = 'Response is' + outAnswer + inAnswer;
MailApp.sendEmail(emailTo, subject, body, {
htmlBody: body});
}
//function that adds the latest response from checkout to check in
section
function addOut(outAnswer) {
//getting check in section item with its choices
var a = form.getItems(FormApp.ItemType.CHECKBOX)[1].asCheckboxItem();
//getting choices from check in
var choices = a.getChoices();
//creating new choice for check in
var choice = a.createChoice(outAnswer);
//adding the choice to the choices
choices.push(choice);
//setting the choices with new choice for check in
a.setChoices(choices);
}
//function that deletes answer from checkout
//only works when its a string so convert outAnswer to string value with
toString but only works with a single choice
function deleteOut(outAnswer) {
var del = form.getItems(FormApp.ItemType.CHECKBOX)
[0].asCheckboxItem();
del.setChoices(del.getChoices().filter(function (choice) {
return choice.getValue() !== outAnswer.toString(); }));
}

Answer 1

You're going to need to do the same kind of thing as the spreadsheet answers suggested, create a script lock and use it to dump quick successive triggers.
Just add the following lines to the top of your script:
var lock = LockService.getScriptLock();
try {
lock.waitLock(3000);
} catch (e) {Logger.log('Could not obtain lock after 3 seconds.');}
Utilities.sleep(3000);
You can also add a "lock.releaseLock();" to the end of your script, but it isn't necessary, locks release on their own.
All this code does is reject any new submissions in the next three seconds after it is triggered. If that isn't enough, change the time in the waitlock AND the sleep to 5000 (forms generally take less than three seconds to run a script like this so you are forcing the script to take longer).