Common Issues and Troubleshooting
Solutions to common problems with the MUP Compliance App.
Cart Transform Issues
Levy Not Being Added
Symptoms: - Product added to cart - No levy appears - Price is below MUP floor
Solutions:
1. Verify customer has selected Scotland as region
2. Check product has custom.total_units metafield
3. Ensure MUP enforcement is enabled in settings
4. Verify levy product is published to Online Store
5. Check browser console for errors
Wrong Levy Amount
Symptoms: - Levy is added but amount is incorrect - Doesn't match expected calculation
Solutions:
1. Verify total_units metafield is correct
2. Check minimum unit price setting (should be 0.65)
3. Review product price
4. Calculate manually: (units × 0.65) - price
Levy Added Twice
Symptoms: - Multiple levy line items for same product - Duplicate charges
Solutions: 1. This should not happen - contact support 2. Clear cart and try again 3. Check for multiple cart transform runs
Validation Issues
Validation Not Added to Checkout Rules
Symptoms: - Validation function not blocking checkout - No validation errors shown - Function not appearing in checkout rules
Solutions: 1. Go to Shopify Admin → Settings → Checkout 2. Check Checkout rules section 3. Verify "MUP Validation" function is added 4. If not, add it following the setup guide 5. Ensure function is enabled
Checkout Blocked Incorrectly
Symptoms: - Checkout blocked when it shouldn't be - Error message appears incorrectly
Solutions:
1. Verify product total_units metafield
2. Check minimum unit price setting
3. Review discount code configuration
Checkout Not Blocked When It Should
Symptoms: - Order completes despite MUP violation - No validation error shown
Solutions: 1. Ensure MUP enforcement is enabled 2. Verify customer region is Scotland 3. Check validation function is active 4. Review product prices and units
Region Selector Issues
Selector Not Appearing
Symptoms: - Region selector not visible - Can't select region
Solutions: 1. Check theme customizer settings 2. Verify app embed is enabled 3. Review CSS selector configuration 4. Check theme compatibility
Region Not Saving
Symptoms: - Select region but it doesn't save - Cart doesn't update
Solutions: 1. Check browser console for errors 2. Verify cart update is working 3. Review cart attribute format 4. Try refreshing page
Product Data Issues
Units Not Recognized
Symptoms: - Product has metafield but not used - Levy not calculated
Solutions:
1. Verify metafield namespace is custom
2. Check key is exactly total_units
3. Ensure value is a number (not text)
4. Verify product is saved
Health Check Shows Missing Data
Symptoms: - Health check reports missing data - But metafield exists
Solutions: 1. Re-run health check 2. Verify metafield on correct variant 3. Check metafield value format 4. Ensure product is published
Settings Issues
Settings Not Saving
Symptoms: - Click save but changes don't persist - Settings revert
Solutions: 1. Check admin permissions 2. Verify Shopify connection 3. Refresh page and try again 4. Check for error messages
Levy Product Not Working
Symptoms: - Levy product configured but not used - Error when adding to cart
Solutions: 1. Verify product is published to Online Store 2. Check variant ID is correct 3. Ensure product is not archived 4. Verify product is active
General Issues
Extensions Not Working
Symptoms: - MUP features not functioning - No errors visible
Solutions: 1. Verify MUP enforcement is enabled 2. Check customer region is set 3. Review browser console 4. Check extension deployment status
Performance Issues
Symptoms: - Slow cart updates - Delayed levy calculation
Solutions: 1. Check network connection 2. Review cart size (many items may slow) 3. Check Shopify API rate limits 4. Review extension logs
Getting More Help
If issues persist:
- Check Logs:
- Browser console for frontend errors
- App logs for backend errors
-
Shopify function logs
-
Review Settings:
- MUP settings configuration
- Metafield definitions
-
Product data
-
Test Scenarios:
- Simple test product
- Known good configuration
-
Isolated issue reproduction
-
Contact Support:
- Provide error messages
- Include relevant logs
- Describe steps to reproduce
Debug Mode
Enable debug mode to get more detailed information:
- Set
custom.mup_debugmetafield totrueon shop - Check console/logs for detailed output
- Review cart transform and validation logs
See Debug Mode for more information.