Please help!

I’m currently working on a pattern for a baby’s cabled sweater, but am now stuck on something which seems quite simple. Really hoping someone can help. I’m now on the sleeves, it asks me to cast on 48. Then row 1 is k2, yfwd, k2tog, *k 1, sl1, k1, psso, yfwd, k8, yfwd, k2 tog, rep from * to last 5 stitches, k1, sl1, k1, psso, yfwd, k to end.
Row 2. P4, k1,*p12, k1 rep from * to last 4 stitches, p to end.
The problem i have is i cast on 48, then at the end of row 1 i still have 48, but as i come to the end of row 2, i p 12, but where there should be 5 sts left, so i can k1, then p 4, there are only 4 sts left? When i recount my sts i only have 47?! So i’m obviously doing something wrong but can’t for the life of me figure out what it is, i’ve attempted this 6 times now, please help

You might have dropped one of the yfwd/yos somewhere.

you must be “eliminating” one stitch either on row 1 (forgetting a yfwd anywhere? maybe at the end of the whole thing after the repeat?) or you must be dropping / skipping something on row 2.

48 are cast on and row 1 has one increase per one decrease to it remains 48.
48 and the math of row 2 line up, so 48 it must be!

check on yourself: whenever you make a (sl1,k1, psso) or a (k2tog) in row 1 you also make a yfwd right before, respectivly right after that (after the sl1,k1,psso / before the k2tog). Did you do that?