Ja Nai Hou no Hakushaku Reijou: Hitochigai de Kyuukon sareta node Hadan ni Shite Sashiagemasu

Liosette Madal, the only daughter of the count's family, is facing her sixth broken engagement. The reason is that a popular young lady, Liosette Dadel, has a similar name?! Since unmarried women usually can't show their faces and proposals are done through letters, Liosette has no shortage of suitors mistaking her for the wrong person. All she can do when she realizes they've made a mistake is to avoid hurting their pride and reputation by asking to break off the engagement. But then Liosette, already used to broken engagements, receives a proposal from the reknowned elite duke Loris Visant. She thinks she'd better let him know quickly that he's made a mistake and break it off, but Loris is serious about "Liosette" and pursues her intensely...?

(Source: Shusuisha, translated)