CRJ700 pilot reported cabin door latching mechanism was not properly positioned prior to flight.

Narrative

I was PF (Pilot Flying)/Captain from ZZZ1-ZZZ. The crew got on the plane; and I was busy doing the first flights; getting fuel and water; and doing our best to get thing going on time. We got the on-time and pushed off the gate/got a runway change/dealt with cabin air temperature issues requiring manual override of Pack 2 the whole way to ZZZ in an attempt to cool down the cabin. The plane also had a lousy passenger cabin door seal; and made a horrendously loud whine the whole way to ZZZ. Reaching ZZZ; I wrote up the malfunctioning Pack outflow sensor/temp control; the door seal. I got off the plane to explain to the next Captain what the pack had been doing in flight; and at this point; my Lead FA (Flight Attendant) asked if I was going to 'write up the door.' I told her I had written up the passenger door seal; and she asked me if I was going to write up the galley service door. This was the first I had heard of any issue with the galley service door. The Lead FA then told me that on the ground in ZZZ1; while I was using the lav just prior to pushback; she had told my FO (First Officer) that galley door wasn't green or similar wording. As relayed to me; our FO looked at the doors page; saw it as green and told the FA it was green (which it was). She also told me that a previous crew Captain told her the door marks didn't matter. When I asked her if she was talking about the green witness mark on the door; she had no clue what that meant. I then took her on the plane and had her physically show me what she was talking about (green witness mark). She pointed to the witness mark; which was not properly displaying green in the locked door position. I explained what the green marks aligning indicates; and explained that it was possible the door was not locked properly. She looked like she wanted to cry. When I asked the FO; he said our FA had not mentioned anything about the galley service door. I added the missing/damaged paint on the service door witness mark to the maintenance logbook so it could be addressed. My FA used confusing language and didn't explicitly state which door indication she believed was not working properly. The two door indications are both green; and this confused my 67 hour FO. The FA also told my FO while I was in the bathroom (at the gate; with door open) and neither of them brought me into the loop. My FA didn't understand basic functionality of a door that she is responsible for; and had also been given inaccurate information by a previous Captain. I had a conversation with my FO that ANY concern about aircraft issues brought to their attention while the Captain is not present with worth mentioning. I had a very extensive conversation with the FA about how the door worked; demonstrated what the witness mark is supposed to indicate; talked with her about advocating for her own safety and politely asked that information is shared with the Captain directly; especially when the FO is so new.