It is not a symbol as such, it is just a symbol line type.
And because the post is round, the line will curve as well giving that strange look.
So instead of using a straight or dashed line, you are using a symbolic line.
If it is happening all of the time then the default line type that has been set for your post is using the wrong line type.
Or possibly you have changed the line type that is used by the post.
Lines are referenced by index number - although we see the names.
So say the post was set to use line type = short dash which has an index number of '5', and you have managed to changed line type 5 to be a symbolic line like a zig-zag (either in the line type settings or via the Attribute manager), then the post will now use the zig-zag line.
Barry.
One of the forum moderators.
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