Army and navy cannot be stationed in the same city and be in the garrison (Rome 2)?

An issue came up for me recently, when garrisoning an army and a navy in the same port town (Alalia). Whenever I would fight a battle in the city , either my army or my navy (whichever was not the leader of the battle) would be reinforcing from the outside of the map, rather than starting in the city with the garrison. Additionally, when I had an army and a navy in Alalia, the army could be attacked on the campaign map, without reinforcements from the garrison or the navy stationed there. The result was a field battle. Has anyone had this issue?