Quick fix: Wind the working yarn one extra time around your index or middle finger to add resistance, then check that the yarn isn't pulling from a loose ball at a strange angle.
What you are seeing
Your knitting starts firm and even, but as you continue the fabric grows looser and slightly floppy. The rows at the top look different from the rows at the bottom. When you measure gauge, it's drifted from what you swatched.
Why it happens
- Relaxing too much as you get into the rhythm — your hands loosen without you noticing
- The yarn ball unwinding and pulling at a different angle as it gets smaller
- Switching from working standing or seated differently, changing arm position
- Knitting more quickly as you warm up — faster knitting often produces looser stitches
- Using slippery yarn (bamboo, silk) that requires more resistance to stay at the right gauge
Fix it now
- Check your yarn path — is the ball rolling around freely or sitting at an odd angle? Place it in a bowl or yarn bowl to control the angle it feeds from.
- Add one extra wrap of yarn around your yarn-holding finger to create more resistance.
- Slow down deliberately for the next 10 stitches and focus on keeping consistent pull on the yarn.
- If the loose section is very visible: frog back to where the tension changed and re-knit at a consistent pace with more yarn control.
Prevent it next time
- Use a yarn bowl to keep the ball stable and the yarn feeding at a consistent angle
- Check gauge every 20 rows by laying a ruler across the fabric — catch drift early
- Knit at a consistent pace; slow down when you feel yourself speeding up
- If using slippery yarn, try continental knitting style — yarn held in the left hand gives more natural tension control