@Reginaphalangeeeee I am also right in the middle of a horrible cold/flu virus, so I am with you there. I haven't been thinking about what I'm eating, and I'm not able to do anything other than sit around feeling crappy. So no exercise at all for the last few days.
I started at a similar weight to you, at 139kg, back in July 2024, so I am about 6 months ahead of you I think. It took a similar amount of time to lose 25% of my starting weight, and my weight loss has definitely slowed right down since then. Over the last month or so I have lost 1.4kg and it has taken me around 12 weeks to lose 6kg too.
Not many people on the clinical trials lost as much weight as you already have, and very few lost the percentage amounts that those of us on longer journeys need to. Mainly because there were not many people who started with the kinds of BMIs that we had. So I think it's relatively uncharted waters! Losing literally half your body weight is a big big task and will require a lot of change for our bodies to get used to.
Also, being poorly will have an impact on weight loss. There will be virus related inflammation for sure and everything will just be out of sorts. I wouldn't make any decisions or judgements until you are well and back on it.
A 600 cal deficit daily will eventually see weight loss resume. It's always worth double checking calorie counts to make sure that your totals are accurate and that your TDEE calculation is up to date.
At this point, rather than drop the calories further, can you increase activity at all?