LTC7149 problems

i have some problems with the LTC7149EUFD#PBF. 

I am using this regulator to convert 24V input to -5V output.  I designed the schematic based on the datasheet and i simulated the schematic with the LTSPICE. It worked well.

But during testing, when i gave an input of 5V, the obseved output was  -1.026V.  When the input gradually increased to 24V, the output did not change, still at -1.062V.

I measured the waveform of the output voltage (VOUT-) at the startup of the regulator, and I inserted the schematics and the measured output response waveform in this post.

Could you please give me some comments on this?

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