It seems to me that if China wants to promote positive relations with South Korea how about they apologize for destroying the ROK during the Korean War?:

President Lee Jae Myung has said that South Korea and China should work to ease negative public sentiment toward each other and develop “good neighborly, friendly” relations to help expand economic cooperation.
Lee made the remarks at a welcome dinner hosted by Shanghai Party Secretary Chen Jining after arriving in Shanghai on Tuesday — the second and final stop of his state visit to China.
“I believe building good neighborly, friendly relations is essential when it comes to resolving economic issues,” he told Chen.
He noted that “unfounded and unnecessary misunderstandings” have long hurt public sentiment in both countries and have become a factor hindering the development of bilateral relations.
“We need to minimize those misunderstandings and encourage more goodwill between our peoples,” Lee said. “If there are areas of conflict or confrontation, we should minimize them and maximize the areas where we can benefit each other so that we can truly become good neighbors.”
You can read more at the link, but there is no misunderstandings; China almost completely destroyed the ROK during the Korean War. After they were unsuccessful in that venture they have continued to back the North Korean regime which has launched countless provocations against the ROK over the past 7 decades leading to the deaths and disappearances of hundreds of Koreans. China has also on multiple occasions tried to economically bully South Korea with the THAAD issue being the latest example.
Or how about China apologize for what they did in 2008 when the Chinese Embassy bussed in Chinese students to attack and beat down Koreans protesting in Seoul for Tibetan freedom? Or how about apologizing for the Chinese fishing boats that continue to loot South Korean waters and have attacked and murdered Coast Guard personnel? China is even trying to claim Korean territory as their own. The Chinese then even fly bombers in coordination with the Russians through the Korean ADIZ to intimidate the ROK. None of this seems like a misunderstanding to me, it is bullying and I don’t expect it stop no matter how many nice things President Lee says about China.









