Assigned report templates not working

Ive had different report templates for different services. They were working totally fine for weeks but since yesterday all my service reports keep using the default report. For now I’ve just been continuously switching which template is the “default” one so I can send my clients the right report, and that function works fine. I’ve also tried unassigning and reassigning services to templates but it still uses the default. Hopefully that makes sense

Anyway, I know you are fairly quick with fixes like this so just want to thank you in advance, I appreciate your time!!!! :-)