If none of the lives were added, most probably you have the maximum amount of lives at the moment. When you start the game, your limit of lives it set to 5. If you try to accept more lives from your friends or buy lives, they won’t be added*.

That also explains why only some lives from your friends may be added: the lives were filled up to the limit and all extra lives disappeared.

* Please note that when you win a life in the Wheel of Fortune it will be added regardless of whether you have the maximum amount of lives or not.