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Recently, a single-line spectroscopic binary, LTD064402+245919, has beendiscovered by Yang et al. Using data from LAMOST and ZTF, the unseen companionis estimated to have a mass of 1-3 $M_{\odot}$, orbiting a subgiant withorbital period of 14.50 days, making it a good compact binary candidate withoutX-ray emission. However, new light curves from ZTF and ASAS-SN, have shown thedepth of one dip increases towards a bluer wavelength, indicatingLTD064402+245919 is more likely to be a subgiant with a red star. Using bothWilson-Devinney code and Phoebe, the derived $T_{eff}$ of secondary is about3400 K, corresponding to a red M2/3 star. Additionally, the 20% error ofparallax from Gaia is large. The mass of subgiant will be 1.28 $M_{\odot}$instead of 2.77 $M_{\odot}$, if the refined distance of 5.0kpc is used.Nevertheless, new multi-colour photometry are warranted for the finalconfirmation of binary properties.

LTD064402+245919, compact binary or subgiant with red star eclipsing binary?