Maclaren Triumph- help!

[maybemum2]

I have just purchased the MacLaren Triumph stroller and I am having trouble with the recline feature. I’m not sure if this is just the way it is or if I’m being stupid!
It is advertised as having a multi level recline. The manual and information I can find online shows this is adjusted with a sliding string/strap thing. I’ve done that but it hardly makes any difference, only a couple inches. This can’t be the multi level recline can it? I am less concerned with it being lie flat- my problem is that I can’t seem to get it upright enough. The part of the seat that the bum goes on is also quite shallow so that plus the steep recline basically means my toddler is sort of slipping out and leaning back and can’t see what’s around him that well. I haven’t measured the angle of the recline but I would estimate it’s about a 45 degree angle, whereas I’m wanting about a 70 degree angle (90 being completely straight).
There is some Velcro on the back of the seat and I can’t find where it could be meant to attach to. I thought maybe there was something I was missing about how the recline could have a larger range. It just doesn’t make sense that it is like this. I’ve watched the MacLaren YouTube video which very briefly shows the recline and they use the pull string but the range is much larger than what I’m getting. Anyone know what I could be missing?