I also have the Koala cuddle band and we love it. Very easy to use and feels really secure perfect for newborn stages
Second the group Jess suggested, they've been awesome! I got the Close caboo second hand from Vinted when my son put more weight on, we started using a sturdier carrier.
I’ve got the Moby Classic Wrap and love it x
Close caboo
We’ve got the koala cuddle band and it’s great. You could always post a fit check on the Baby Wearing U.K. FB group (or search for your sling and see if someone else has posted) as you’ll probably get some great tips and be able to continue using!