Illustrator line issue

[Gunes Ozcan_work]

My illustrator is updated and just in case I restarted, but nothing changes. Here is a line looks weird, see attached image. Other lines on the screen are just fine. And if I use eye-dropper and pick the same thickness from another line, the line looks thicker than others and it is huge - see the second attached image. Do you know what is going on? Thx.

[Monika Gause]

Looks like the calligraphy stroke issue.

You can try and apply the zigzag effect to the path.

First option in there must be 0.

The other option must be high (think like at least 50 if not 100)

[Gunes Ozcan_work]

that worked! thank you Monika!