For hypercalcemia I have read that one should increase rather than decrease calcium. A little insight please?

High Calcium Levels. The most important part of your question is the word "hypercalcemia". You need to go to a physician to find out the cause of your high levels of calcium (hc). You need to be investigated for hyperparathyroidism and need to have metastatic cancers of the bone and breast, among others, ruled out. Patients with hyperthyroidism can have hc as well. Thiazides can also cause hc. See a doctor.
If you are. Referring to ca++ intake in the diet in the face of high blood levels the answer is one would stop any ca++ supplements, but major dietary changes are not needed as gut absorption plays a minor role in the blood level.