Articles on: Dynamic Number Insertion (DNI)

Troubleshooting Google Tag Manager call tracking issues

This guide covers the most common reasons the Nimbata DNI script fails when deployed via Google Tag Manager (GTM), and how to fix each one.


For setup instructions, see: How to activate the DNI script via Google Tag Manager.


The number is not swapping at all


Check 1. Confirm the GTM container is published


Changes in GTM do not take effect until the workspace is submitted and published.

If you added or updated the Nimbata tag but did not click Submit, the change is not live.

  • In GTM, click Submit and then Publish.
  • Revisit your website and test again.


Check 2. Confirm the tag trigger fires on all pages


If the trigger is scoped incorrectly, the tag only fires on specific pages - often just the homepage.

  • In GTM, open the Nimbata tag.
  • Check the trigger. It should fire on Page View - DOM Ready > All DOM Ready Events.
  • If it is scoped to a URL match or specific page, update it to fire on all pages (or all pages where your number appears).


Check 3. Confirm Tag firing options is set to Once per event


  • In the Nimbata tag, expand Advanced Settings.
  • Set Tag firing options to Once per event.
  • Save and republish.


Check 4. Confirm the DNI ID is correct


  • Go to Tracking > Tracking Code in Nimbata.
  • Copy the DNI ID (the value highlighted in green in the script tag).
  • In GTM, open the Nimbata tag and confirm this value is entered in the Dynamic Number Insertion ID field exactly as it appears.


Check 5. Click Save & Publish in Nimbata first


The Nimbata script must be saved and published in your Nimbata account before GTM can load it.


If you made changes to your swap targets or advanced settings but did not click Save & Publish in Nimbata, those changes are not live even if GTM is correctly configured.


The number swaps on the homepage but not on other pages


This is almost always a trigger scope issue.

  • Open the Nimbata tag in GTM.
  • Change the trigger from a URL-specific page view to All DOM Ready Events.
  • Submit and publish the container.


The number swaps on a direct visit but not on Google Ads clicks


The DNI script is loading correctly, but the Google Ads swap group is not triggering.

The most likely cause is that the gclid parameter is being stripped.

  • Click one of your own Google Ads and check whether gclid= appears in the browser address bar after the page loads.
  • If it does not, a redirect or caching layer is removing it.


Common causes include HTTP-to-HTTPS redirects, www to non www redirects, and CDN or caching plugins (Cloudflare, WP Rocket, Varnish) that strip query string parameters.

  • Fix the redirect chain to preserve query strings.
  • If you are using Cloudflare or a caching plugin, confirm it is not configured to ignore or strip URL parameters.


Detailed Guide: DNI: caching and CDN issues (Cloudflare, WordPress caching, server cache)


The number swaps but then disappears or reverts


This happens on Single Page Applications or sites with dynamic content that re-renders after the swap has already fired.

  • Open the Nimbata tag in GTM and confirm it fires on DOM Ready, not on Window Loaded or a custom event that fires before the full DOM is available.
  • In Nimbata, go to Tracking > Tracking Code and enable SPA mode under Advanced Settings.
  • Save & Publish, then republish the GTM container.


GTM preview shows the tag firing but the number still does not swap


The tag is loading but the swap itself is failing. This is a Nimbata configuration issue rather than a GTM issue.

  • Confirm your swap target in Tracking > Tracking Code matches the phone number in your page source exactly.
  • Use the built-in website URL checker in the same page to test detection.


Detailed Guide: DNI: swap target formatting rules and common mistakes



Consent banners (OneTrust, Cookiebot, CookieYes, and similar) can prevent GTM tags from firing until the visitor accepts cookies.

If Nimbata is categorized as a tracking or analytics script, it will be blocked for visitors who decline.


  • Open your site in a fresh browser session without accepting the cookie banner.
  • Open the browser console (F12 > Console) and check whether the Nimbata script loads.
  • Review how your consent tool categorizes the Nimbata GTM tag.
  • If appropriate and compliant with your privacy policy, re-categorize it as Functional or Necessary.


Consult your legal team before changing cookie categorization.


Still not resolved?


Submit a request via ? > Submit a request in your Nimbata dashboard. Include:

  • Your website URL and which page(s) the number should swap on.
  • A screenshot of your GTM tag configuration (trigger, firing options, DNI ID).
  • Whether ?gclid=test appended to your URL produces a swap.
  • The output of your browser console (F12 > Console) when visiting the page.


Detailed Guide: How to activate the DNI script via Google Tag Manager

Detailed Guide: DNI: full troubleshooting guide - numbers not swapping on your website

Detailed Guide: DNI advanced settings explained

Updated on: 05/05/2026

Was this article helpful?

Share your feedback

Cancel

Thank you!