RIC only lists the mintmark SMANI for the Constantinopolis issue, but does have SMANTA for a Constantine I GLORIA EXERCITVS issue (RIC 85) and this coin should come after it.
Constantinopolis
A.D. 335
18x19mm 2.4gm
Obv. CONSTAN-TINOPOLIS laureate, helmeted, wearing imperial mantle, holding scepter.
Rev. Victory stg. l., on prow with spear, shield.
in ex. SMANTI
RIC VII Antioch –-
other examples--
https://www.forumancientcoins.com/notinric/7ant-85_cp.html