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By default, office hour default by global settings.
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a. Select （1）Select the Default by specific settings
Office hours with specific settings has higher priority than global setting.
b. Select （2）Select your Time Zone.
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c. On （3）On the Working Hours tab, add your working hours for the days on which your customer service team is working.
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d. On （4）On the Holidays tab, click the Add Holiday button to set your holidays. You can also remove an existing holiday from the Operations column.
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e. Click （5）Click Save.