Updating Minix 8H Kodi 15.1 To Kodi 16.1

Could somebody please help me. I am trying to update my Minix-8H box from Kodi 15.1 to 16.1 (I know that release 17.1 is released, but first things first). I have previously updated Kodi 15.1 from XMBC & all went well. I have downloaded Kodi 16.1 apk
to a USB stick & the Minix box. Which ever one I use to install the apk , usimg option new or all, the following message appears, after failing to load “An existing package by the same time with a conflicting signature is already installed” I expected the file to install & overwrite the existinh Kodi 15.1 to 16,1 & keep my existing settings. Does this mean I have to delete Kodi 15,1, losing all my settings & start again ?

Many Thanks