Afghan pattern misbehaving

My pattern calls for 121 stitches. After 6 rows of garter stitch, the first two rows are P2, K2 to the end of the row. The third row calls for P1, *K2, P2; repeat from *. End K2, P1. However, there are 4 stitches at the end of the row and this throws off subsequent rows - I had to pull out a bunch. Is this something to do with circular needles or is the pattern faulty.
Many thanks.

Hmm…what pattern is it… do you have a link?

Yes, which pattern? There could be a typo in either the number of sts to cast on or how you work them.

It’s a Coats pattern - Quick Knit Blanket - 928-0650. The picture has a zig zag knitted rib along the length of the afghan, so maybe the pattern is correct and I should follow it regardless of how the row ends up?
Cast on 121 - garter stitch 6 rows
Row 1 and 2 - P2,K2; rep from
Row 3 - P1, K2,P2; rep from. end K2,P1.
Row 4 - K1, P2, K2; rep from. end P2,K1
Row 5 and 6 - *k2,P2; rep from *.
Plus more repeats to 16 rows and then repeat the lot.
Many thanks.

I can’t find the pattern, but if I had to guess I’d say the cast on is incorrect. :??

I agree with Jan, the sts work better with a CO of 120

Rows 1 and 2 cannot be done as written. “P2,K2” requires an even number of stitches (in multiples of 4, actually), so either your cast-on is wrong and probably should be 120, instead of 121, or they left off a stitch in the directions. Either a K1 at the beginning or a P1 at the end of the row,most likely, depending on how the pattern is supposed to turn out.

The other rows also require a multiple of 4 sts too, so it looks as though it’s the cast on number that’s wrong and should be 120.

Are you sure there isn’t a K1 or P1 at the beginning of each row, before you do the K2P2 repeats across the row? This would allow for a seed stitch pattern, instead of ribbing. There seems to have been one at the beginning of row1.

Yes, there’s a single knit and purl at the beg of rows 3 and 4 (not row 1) but there’s also 3 knit and purl sts at the end of those rows, which still make the stitch number a multiple of 4, not 4 plus 1. This isn’t a seed st, it’s a diagonal rib, where you move the 2x2 rib over a stitch every other row.