Which of the following is not a feature of pseudohypoparathyroidism?

Pseudohypoparathyroidism ( PHP ) is a group of inherited disorders characterised by hypocalcemia and hyperphosphatemia. Hypocalcemia is due to resistance to parathyroid hormone, which results in hyperplasia of parathyroid glands, and thus causing elevation of PTH levels. Reference: Harrison 21st edition, page 2485