Help with gauge please

Hello to my fellow knitters. I am hoping someone can help me with a teensy problem. The tension is listed as 24 sts and 36 rows to 10cm over stocking stitch on #5 needles. I have done this and my tension comes out to - 10cm across and 12cm down. Is it supposed to be a 10cm square? If so, how can I fix it. I am making a purse using silk yarn and I don’t think I need to worry about the length so I am assuming I should be ok with the tension I have? I sure hope so.

It’s generally a good idea to CO more sts than you need to make the 10cm/4", so 30 sts would be good to do and don’t include the edge sts when you measure. They’re a different size than the middle sts and curl under. So you should get 24 sts over 10cm across and 36 rows in 10 cm up and down. Hardly anyone gets both row and st gauge right, but the sts are more important as you can knit less or more rows to get the length which is usually given as a measurement anyway. is an article from Knitty that really helped me with guage swatching.