Thanks for sharing the QR.
Please note that, if you have images with very accurate geotags (RTK/PPK datasets), you need to adjust the x,y,z accuracy values (Accuracy Horz and Accuracy Vert) in the Image Properties Editor . The default accuracy in Pix4Dmapper is 5 m and 10 m as you can see in the screenshot below. When using RTK/PPK technology, the image accuracy should be much better (few centimeters - 0.02 m is usually set for the vertical and horizontal accuracy). Please check that the accuracy of your images is set correctly in the Image Properties Editor, because the software needs to know how much to trust these coordinates, so setting the correct accuracy is crucial. This community post can shed some light on this topic: Accuracy of image collection with RTK.
One other factor to consider is the coordinate system used in this project (OSGB 36). If a horizontal coordinate system transformation is required to accurately transform your project’s Image Geolocation Coordinate System or GCP Coordinate System to your project’s Output Coordinate System, you must transform your project’s inputs’ coordinate system to your project’s Output Coordinate System before processing your project. Please follow the steps from this community post and let us know if the project results have been improved: Horizontal grid corrections and transformations.
Hopefully this helps.