When you are using latest Google Analytics Code and latest Google Ads Conversion code in your website, there could be multiple global site tag installation conflict.

Old Google Analytics Code looks like as given in below screenshot

Latest Google Analytics Code looks like as given in below screenshot

So when using the latest google analytics code, use the following setting in your google ads conversion code setup 

Now add this code to your google analytics code as shown in below screenshot

Leave the Global site tag field empty in Google Adwords setting