Oracle Error Message
ORA-54521: inner ring is not inside or is touching outer ring more than once
Reason for the Error
An inner ring either was not inside its outer ring or touched its outer ring more than once.
Solution
Ensure that the inner ring is inside its outer ring and does not touch the outer ring more than once. If an inner ring touches its outer ring more than once, then the outer ring is no longer a topologically simple or singly connected polygon (ring).