ADM7150ACPZ-5.0 damage.

My voltage regulator

worked properly some length of time, but one day at switching on it was spoilt. The voltages (measured by multimeter) are:

VOUT ….  1.26V ,

BYP ……   1.26V,

VREG…….5.5V ,

REF and REF_SENSE ….5V

Chip was replaced by new one and again voltage regulator worked properly some length of time, but one day at switching on it was spoilt as well.

What may be a reason?

Thank you in advance.