"Are there any fixed format through the domain registration with Todayisp.com?"

--Yes.

Firstly, the basic format for telephone and fax number when registering/modifying domains (applicable for all domain extensions) is +[country code].[zip code][telephone number]. For example, if your country code is 86, zip code is 756, telephone number is 3810566, then you should input +86.7563810566. The fax number format is the same. However, for China HongKong, the basic format should be +852.[telephone number], like +852.22190860 by TodayISP. 

Secondly, the address should be less than 64 characters.

Thirdly, the country should be chosen from the drop down menu.

If the telephone/fax format of your domain registration was set as +[country code].[zip code][telephone number], all domain registrars will love you to death as this will save them much time to proceed.

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