Car seat has injured my baby

[Babyblooes]

I didn't really know where to post this, I apologise in advance if this is in the wrong place

I bought a new car seat a few months ago for my daughter who is now one year old.
A few weeks ago I noticed she had a cut on her neck and put it down to a scratch. It started to scab over when the wound opened again and was bleeding and over the next week or so, a few more marks started to appear and old ones kept opening up again. I couldn't work out where they were coming from until I was getting her out of the car seat last week and when I loosened the straps on her car seat she started to scream. I noticed that the skin on her neck was getting trapped between the strap and the cover of the strap as I pulled the straps loose.
I'm sure you can imagine the guilt I now feel having realised I've been hurting my child and making her bleed on a daily basis for the past few weeks.
I have emailed the car seat company who have replied asking for photos of injury and other details but I don't really know where to go from here?
Do I put it down to user error and be content knowing that I've made them aware of the problem?
Or do I take it further? I don't even know what else I could do about it?
While I'm deeply ashamed and horrified that I've been hurting my beautiful baby girl without even realising, I'm still very angry that it's even possible for this to happen
Thank you all in advance x

Which seat is it?

It's the Graco Milestones car seat

That sounds like a terrible design to me if her skin could get trapped like that. Don't feel bad though as you weren't to know.
Do you know if it's a new model of car seat? It might be that they have to be recalled if it is.
I would demand a full refund at the very least and ask to know what they are doing to stop it happening to others.

A design fault?

Were there little bits of fabric over the straps at neck height? My ancient car seat has this but I don't know if it's standard

Yeah that's what's confusing me, the straps seem pretty standard. Just a normal strap with a protective cover type thing on but something just can't be right to be hurting her like that. Now I'm aware of it I can make sure it doesn't happen again but I'm still weary of the bloody thing

Trading Standards?

Yeah I think they all have covers like that over the straps, but it must be that the covers are too tight so her skin is getting caught in between, if that makes sense. The covers on ours were really loose. Hope your DD's neck gets better soon.