SLA Response Due Date are not populating automatically

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Hi All,

Here my issue is, I'm getting an Incorrect date in Initial Response Due.

I have configured 600 in Response Requirement, but at an incident level, the response due is set as (3-days, 2 days & 4 days) calculation).

Please refer to the screenshot. 

How to achieve this issue. Please explain me to understand

your help would be greatly appreciated

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