Here’s the answer I would give.
The Church has been Catholic from the 1st century. The English word Catholic is a transliteration of the Greek katholikos which is a compound word from kata, which means according to, and holos, which means whole.
catholic.com/tracts/what-catholic-means
So one THEN can ask, where does kata holos appear in scripture and particularly kata holos ekklesia ?
Acts 9:31 the church throughout all
ἐκκλησία,
καθ’,
ὅλης ,
τῆς ,Judea and Galilee and Sama’ria…" = Kataholos Church.
Ignatius was Bishop of Antioch from ~69 a.d. to ~107 a.d. He was ordained by the apostles, and was a direct disciple of St John. It was in Antioch where the disciples were first called Christian
Acts 11:26 . And Ignatius in his writings uses both “Christian” and “Catholic Church” in his writings.