I do not see any error. If you are referring to the grooves, that is just the normal shape of this token. If you are referring to the date being "7607," that is indicating it was minted in July (07) of 1976 (76). The symbol above "GETTONE" is a mintmark indicating it comes from IPM, Industria Politecnica Meridionale, a communications company in Naples, Italy. Cool Italian telephone token!
I looked not the groove and date the only thing i see was the phone on back was upside down but not sure if that is it.