Not the best start.

According to JYP Entertainment, the group NMIXX's debut showcase has been pushed back due to member Bae testing positive for COVID-19 on February 18.
On this day, the label notified fans "On Wednesday, February 16, Bae displayed symptoms of a sore throat, prompting the NMIXX members to conduct a self-diagnosis kit test. Bae tested positive during the kit test, and as a result, all of the members visited the hospital on February 17 to undergo polymerase chain reaction (PCR) tests. As of February 18, Bae's test results were positive."
The remaining members of NMIXX, including Lily, Haewon, Sullyoon, Jinni, Jiwoo, and Kyujin, have all tested negative thus far, but will remain in quarantine while symptoms are monitored. Additionally, JYP Entertainment assured fans that all NMIXX members had received their second dose of the COVID-19 vaccine and that Bae is currently experiencing only minor symptoms.
JYPE stated, "With regards to NMIXX's debut promotions for their debut single album 'AD MARE,' "NMIXX's debut single, 'AD MARE,' is scheduled to be released on February 22. However, NMIXX's debut showcase 'New Frontier: AD MARE' has been rescheduled for March 1."