GA4 UTM Attribution & WordPress Tracking Debugging

Overview

We are restarting a direct mail campaign using QR codes and require clean, reliable Google Analytics 4 (GA4) attribution.

Each QR code links to URLs containing UTM parameters, for example:

https://justera.co.uk/?utm_source=direct_mail&utm_medium=qr&utm_campaign=test_campaign&utm_content=test_letter

We need a developer to audit, diagnose, and ensure correct UTM tracking and GA4 attribution.

Current Environment
• WordPress (IONOS Managed WordPress hosting)
• Site Kit by Google (GA4 connected)
• GA4 Measurement ID active
• Server-side caching previously active (IONOS Performance Level)
• No Cloudflare
• No MonsterInsights
• No Complianz (currently deactivated)
• Previously had a plugin stripping UTMs via JavaScript (now removed)

Problems We Experienced

1. UTMs were previously being stripped from the URL via a JS file:
/wp-content/plugins/wp-stats-manager/js/wsm_new.js
(plugin now removed and cache flushed)
2. After resolving URL stripping:
• GA4 does not consistently attribute session source/medium correctly.
• In some tests, no g/collect requests fire.
• Sessions sometimes appear as (direct) / (none) despite valid UTMs.
• Realtime reporting is inconsistent.
3. Behaviour has varied between devices (likely due to server-side caching).

Infrastructure has been partially cleaned up, but we need a full technical audit and clean implementation.

What We Need Done

1. GA4 Audit & Correction
• Confirm only one GA implementation is loading.
• Confirm page_view is firing correctly.
• Confirm g/collect requests include:
• campaign source
• campaign medium
• campaign name
• Ensure UTMs are captured on first page load (new session).
• Confirm no duplicate tags or container conflicts.

We are open to:
• Removing Site Kit
• Implementing clean manual GA4 (gtag.js)
• Or implementing via GTM if preferable

2. JavaScript Review
• Confirm no scripts are:
• Calling history.replaceState
• Cleaning query strings
• Removing UTM parameters
• Confirm no theme-level or plugin-level URL manipulation.

3. Caching Review
• Confirm no server-side full page caching is serving stale HTML.
• Confirm no service worker is registered.
• Ensure consistent behaviour across devices/IPs.

4. Final Verification

Provide proof that:
• Fresh private session with UTM URL
• Correct attribution appears in GA4:
• Session source
• Session medium
• Session campaign
• Realtime and Acquisition reports reflect correct traffic source.

End Goal

We need fully reliable attribution for:

QR Code → Landing Page → Apply Click

This is critical for measuring direct mail ROI.

Requirements
• Strong GA4 debugging experience
• WordPress experience
• Familiarity with IONOS hosting
• Comfortable using DevTools and network inspection
• Ability to explain findings clearly

Deliverables

• Clean, working GA4 attribution
• Clear explanation of what was wrong
• Confirmation that infrastructure is stable
• Recommendation for simplified tracking stack (if needed)

If you have experience debugging complex GA4 attribution and WordPress caching issues, please respond outlining:

• Similar projects you’ve resolved
• Your approach to diagnosing this
• Estimated time required