There is an error in the pattern. Between RD4 AND RD5, YOU SHOULD DO THIS.
Ch 3. dc in same stitch. * 1 dc in next 3 stitches, 2 dc in next stitch. Repeat around. Join with a sl into the 3rd chain of the ch 3. (50)

SO instead of it being 50 stitches around it should be 40 through out.

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