Help with bonnet

Im knitting a bonnet but Im having trouble with row 6

The pattern says to cast on 90st

My pattern is from the uk I think

row 6: p5, yrn, p3, p2tog tbl, P2tog, p3, yrn, p4 rep from * fin last rep p5

I looked up a Yrn and its just wrapping it round like a yo making one st extra. Is this correct?
the previous row has yf? what is the difference?

I seem to run out of sts before I can fin with the last p5

any help would be appricated

Yes, it uses UK terms - yrn is is a YO between purl sts. Yf is used when the yo is between knit sts. A yo is just wrapping the yarn around the needle as if working a stitch and doesn’t include a st to ‘anchor’ it, the p3 or p4 after your YOs here will do that. So you p5 * yo, p2, p2togtbl, p2tog, p3 yo p4 and repeat that. However, that last time you do it you’ll have a p5 at the end instead of a p4.

If you have 90sts on row 5, the same as the cast on, then you should have enough sts to work the repeat between the asterisks 5 times plus one more repeat which will end p5 instead of p4. You could try marking off row 5 after the first 5sts and then every 14sts (5 times) with 15sts on the very end. That will make it easier to see if something is going wrong on row 6. As you knit row 6 there should still be 14sts between the markers since the yo’s are balanced by the p2tog’s. Good luck with the bonnet!

I tried it again
Row 5 says : K4, yf, k4, k2tog, k2tog tbl, k4, yf, k2 to last 2sts

I can see that adds up to 90st
but I can’t seem to get the same result with
row 6: p5, yrn, p3, p2tog tbl, P2tog, p3, yrn, p4 rep from * fin last rep p5

I must be doing it wrong again?
I thought it would be straight forward like row 5

Take a look at each st after you complete row 5 and name the sts. You’ll see the k4 and then the repeats yo, k4, k2tog, k2tog, k4, yo, k2 and after the last repeat, ending with k2. It’s 4sts, then 6 repeats of 14sts and then 2sts.
Row 6 is similar. You have 5sts, 5 repeats of 14sts each and then [I]a final repeat of 15sts[/I]. Put in markers as you do row6 and again, name the sts when you finish row 6 and see if you can find where you are going wrong.

row 6: p5, yrn, p3, p2tog tbl, P2tog, p3, yrn, p4 rep from * fin last rep p5

This also uses 90 stitches and here’s how. The repeat between the *s amounts to 14 stitches. You purl 5 stitches then work the repeat 6 times and then purl the last stitch (that makes the last repeat end with a p5). 14X6=84, plus the 5 at the beginning and the extra stitch at the end of the last repeat (so that it also has 5 to keep things symmetrical)=90 sts.

I Get it now Ping a light bulb came on lol

Thank you to every reply!!