If the early Church believed in sola Scriptura, why do the creeds of the early Church always say “we believe in the Holy Catholic Church,” and not “we believe in Holy Scripture”?

29) If the early Church believed in sola Scriptura, why do the creeds of the early Church always say “we believe in the Holy Catholic Church,” and not “we believe in Holy Scripture”?

Irrelevant, the creeds are not saying "believe in the Holy Catholic Church and not Holy scripture," therefore it is incompetent, a lie to say they mean that.

105 The Communion of Saints

Niceta of Remesiana, De Symbolo, 10, ed. A. E. Burn, pp. 48f.

After confessing the blessed Trinity, thou goest on to profess that thou believest in the Holy Catholic Church. What else is the Church than the congregation of all saints? From the beginning of the world, be it patriarchs, Abraham, Isaac, and Jacob, prophets, aposdes, martyrs, or all other just men, who have been, are, or shall be, are one Church because they are sanctified by one faith and life, sealed by one Spirit, made one body; of which body the head is held to be Christ, as indeed it is written. I go further. Even angels, virtues, and powers supernal are united in this one Church; for the Apostle teaches that in Christ all things are reconciled, whether things on earth or things in heaven. So in this one Church thou believest that thou art to attain the Communion of Saints. Thou must know that this one Church is ordered throughout the whole world and to its communion thou oughtest firmly to adhere. There are, indeed, other pseudo-churches, but thou hast nothing in common with them; as, for instance, churches of Manichaeans, Montanists, Marcionites, and other heretics or schismatics. For they have ceased to be holy Churches, inasmuch as they have been deceived by doctrines of demons, and both believe and do otherwise than is required by the commands of Christ the Lord and the traditions of the Apostles. (Kidd, Documents, II, p. 93.)

Niceta (fl. 380–405) was a contemporary and correspondent of Ambrose and a friend of Paulinus of Nola. The document illustrates Western homiletic preaching at this time.- Creeds, councils, and controversies : Documents illustrative of the history of the church A.D. 337-461. 1966. "Based upon the collection edited by the late B. J. Kidd."; "Intended to be a successor to vol. II of the late B. J. Kidd's Documents, published in 1923." (J. Stevenson & B. J. Kidd, Ed.) (140). New York: Seabury Press.

KJV 1 John 2:21 I have not written unto you because ye know not the truth, but because ye know it, and that no lie is of the truth.

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The times of this ignorance God winked at; but now commandeth all men every where to repent:

Behold, I stand at the door, and knock: if any man hear my voice, and open the door, I will come in to him, and will sup with him, and he with me.-kjv