Just wanted to put this on here for the benefit of others who might be in the same situation in future. I was recommended the Panorama test and it came back as insufficient fetal fraction first time and again on the redraw. Although I am overweight and read that was probably the reason I was also worried as had read that the test failing may indicate a bad outcome.
So I asked for the Harmony test (this was successful with my first pregnancy) and have had low risk results first time. Feeling very relieved after 3.5 weeks in limbo. Apparently the fetal fraction was 8% which is within normal range.
Therefore it seems Panorama does throw some strange results for certain people and if you're on the chubbier side bear that in mind if you're choosing between the different brands! (I do appreciate the Panorama gives more info on certain microdeletions that other NIPTs don't so not completely like for like.)