This is because Sri Lanka was a rich source for collecting cinnamon which was very valuable during ancient times. So, the island probably seemed bigger and more important to Ptolemy.
Sri Lanka was a rich source of cinnamon, which was valuable in ancient times. Therefore, the island must have seemed more important and larger than it really was to Ptolemy.
Warning:
I advise you do not copy and paste this answer since this is the exact answer from Edmentum.
