Forum:Field Cards Q

Can a player activate a field card spell even though they have one that is already active? Scenario: Ancient City Rainbow Ruins is active, and effect 4 had been used to draw 1 extra card during the main phase. There after, the fifth effect of special summoning had been utilized to special summon a Crystal Beast Sapphire Pegasus. After these two effects of Ancient City Rainbow Ruins are used, the player wants to use another Ancient City Rainbow Ruins that is in their hand, even though that same player has another Ancient City Rainbow Ruins (Field Spell) that is already active?