Anthonyzappulla,
Free to Play players are supposed to be capped at 20 million population. Due to birth rate changes over the last few months, some were able to rise above these levels. This has now been corrected, and Free to Play players will not rise above 20 million population.
The 300 thousand population login booster is only around while you are a new player. You can safely ignore it, it will stop soon. It's main purpose is to allow players that go premium, to grow their countries faster, by giving them bonus population, while they are new to the game. Because you are a free to play player, the system will automatically remove the 300 thousand people from your country to bring you back to the 20 million population cap. If you went premium, you could keep that bonus population, instead of having it decline back to the 20 million limit.
Signed President of DanNation on LU