Thanks for the chapter!
MC is taking what those two knights are saying too easily. Even if did save them their attitudes are too different from the arrogant and lordly one they had when met. While guy seems nice and truthful the woman doesn't seem that grateful and like she's doing something not use to. Then there's the artifact they're handing over to MC. Considering attitude when took it I'd say the woman at least would prefer leaving it to sit unused in a warehouse rather than turn it over much less go against orders to remove it without permission. Just seems too off for a couple of arrogant knights who serve the government, not the people, and chosen to enforce the government's views would tell someone they hardly know an opposing view on the government's action rather than just blindly follow orders.
Speaking of Beatrix, thought she could only use summoning when in battle, how is she already in her battle outfit? Sword and shield is understandable as not summoned items and were physically carried by her, but not her armor. Poor MC, has caught the attention of and smitten a battle maniac who expresses her feelings with physical moves in battle rather than words. Although typically only focused on her feelings without considering her crush's feelings or that literally trying to beat her views into him.
Could be wrong, but I'd say those two were ordered by someone with a high position to give the sword to MC to frame him for stealing it along with falsifying a report that he either refused to turn it over or stole it from them. Probably haven't met person yet but since MC going against government's plan to allow Lotte to be murdered, interfering with assassins of a foreign government, and has a Diva that isn't known as one of the 72 pillars of Solomon I'd say this is a conspiracy aimed at entrapping and framing MC so can have an excuse to jail or kill him. Will spring trap as soon as he uses sword for something noticeable whether it's fighting Beatrice or something else, whichever comes first.