[GAMEPLAY] Masteries Shield is Erased by Turret Shield

In a recent game as Garen top i noticed that the 50hp shield, gained through masteries, was gone by the time i reached the outer turret. Later I realized while passing the turrets that now provide a shield to passerby the turret shield was applied, however when the turret shield was removed, it also removed the 50hp masteries shield. The "How to Report a Bug" post also says to include a step-by-step guide, so:

1. Set up a masteries page that includes the mastery point allocated to the 50hp shield each respawn
2. Pick Garen as your summoned Champion
3. Run within range of the top turret that provides shield buffs
4. Exit buff range

After that BOTH shields should be gone, as it happened every time I respawned, and not just occasionally.

Thanks for any help!