LMZ31710: Strange Output always about 9V

Dear  Sir or Madam 

I have used the part LMZ31710 in my boards . But at one of them , the output of LMZ21710 is always about  9V , while the input is 12 volts . 

Even the enable net " PE_1P8V_EN" is reset , there is still about 9V on the output where all the beads have been removed . 

This part was working well at the start , however , one day , It's been like this .

What factors can make this phenomenon ?

Here is my schematic ,

Thank you in advance .

best regard,

Anglic