Another reason might be that you used a low-quality filter or editing effect that made the story look blurry. Try posting without any filters or with different ones to see if it makes a difference.
Maybe the image quality you uploaded wasn't good. Or your phone's camera settings were off.
Maybe your phone's camera quality isn't that good or the lighting conditions weren't ideal when you took the pics for the story.
Sometimes it's due to the quality of the original content you uploaded. If the picture or video was taken with a low-resolution camera or in bad lighting, it'll show up blurry on Instagram stories.
One way to fix blurry IG stories is to check your phone's camera settings. Maybe the focus or image quality settings need tweaking. Also, make sure you have a good lighting environment when taking the pictures or videos.
Make sure your phone's camera is clean and set to the highest resolution. Also, good lighting helps a lot.
Another reason might be that the original photos or videos you uploaded weren't of high quality. If they weren't clear to start with, they'll look blurry on IG stories. Also, sometimes the IG app itself might have glitches that affect the display quality.
It could be that the story has too many subplots or complex characters that make it hard to follow and seem blurry. Another reason might be inconsistent pacing.