Is it possible to use the same hashtags on other campaigns?

You cannot use the exact same hashtags for the same campaign period, on the same social media channel, in the same country.

It is possible to use the same two hashtags at most though (as per the example below) but it is recommended not to:

Example: Campaign A ＃Hashtag1, #Hashtag2, #Hashtag3

Campaign B ＃Hashtag1, #Hashtag2, #Hashtag4　→OK ＃Hashtag1, #Hashtag2, #Hashtag3, #Hashtag4　→× NOT OK