Hi Maygold and welcome to the forums.
Personally, I've not had that experience. Others on here have reported similar to yours- reducing sugar alone has some impact, but not as much as expected.
It's possible that a couple of other things are in play. One is that the issue for many of us in dealing with higher blood glucose levels than we'd like is that it's necessary to take into account all the starchy carb food items that are digested to glucose, not only the obvious "sugary" ones. And there are carbs hidden in a lot of processed and packaged foods which are not so obvious. So in my case that has meant eliminating bread, rice, pasta, potatoes, cereals, beer, fruit and fruit juices, pastry, etc. I didn't really reduce sugary stuff as I wasn't eating very much of that anyway.
The other thing is that there's a level of acceptable error in HbA1c measurements as there is in most things, and your two readings are close enough to be essentially the same. The actual figure depends on your particular healthcare system but many set the level around 6%. So for a true A1c value of 44, results between 41-42 and 46-47 would be acceptable with a variance of about 2.7 either way.
If you've lost a few pounds it's probable - it's certain - you're doing something right. It might need only a very small reduction in starchy carbs (if that's what the issue is) to see bigger changes. What would you normally be eating in a given average day?