Google Sheet Script Not Reliably Running - google-apps-script

Question

I've gotten to the point where I have a pretty solid script that:
1) Takes data from a new data tab and posts it to an existing data tab
2) Clears data from the new data tab
3) Deletes duplicates from the existing data tab
When I originally put this script in, it worked great. But after running it a few times, it seems to stall at the de-duping portion of the script. So when I run it, the first two scripts run, but not the third. If I select the de-dupe script to run on it's own, it works just fine.
Has anyone else seen this issue? Is there any way to tweak the script to have a more reliable run so that it will always process all three scripts?
Not sure how to optimize from there.
function Run(){
insert();
clear1();
removeDuplicates();
}
function insert() {
var ss = SpreadsheetApp.getActiveSpreadsheet();
var source = ss.getSheetByName('Candidate Refresh'); // change here
var des = ss.getSheetByName('Candidate Listing'); // change here
var sv = source
.getDataRange()
.getValues();
sv.shift();
des.insertRowsAfter(1, sv.length);
des.getRange(2, 1, sv.length, source.getLastColumn()).setValues(sv);
}
function clear1() {
var sheet = SpreadsheetApp.getActive().getSheetByName('Candidate Refresh');
sheet.getRange('A2:K100').clearContent()
}
function removeDuplicates() {
var sheet=SpreadsheetApp.getActiveSheet();
var rows=sheet.getLastRow();
var firstColumn=sheet.getRange(1, 2, rows, 1).getValues();
firstColumn = firstColumn.map(function(e){return e[0]})
var uA=[];
for (var i=rows;i>0;i--) {
if (uA.indexOf(firstColumn[i-1])!=-1) {
sheet.deleteRow(i);
}else{
uA.push(firstColumn[i-1]);
}
}
}
All three scripts should fire when the Run script is played.