Here.
1 Corinthians 15:34 BSB
34Sober up as you ought, and stop sinning; for some of you are ignorant of God. I say this to your shame.
And here's the context so you can see he's telling them to stop sinning in regard to not believing the gospel of a risen savior that he preached to them and by which they were saved. You'll see there's nothing here about sinning in regard to moral behavior, but rather what they believe about the resurrection of the dead, specifically Christ:
1 Corinthians 15:12-34 BSB
12But if it is preached that Christ has been raised from the dead, how can some of you say that there is no resurrection of the dead?
13If there is no resurrection of the dead, then not even Christ has been raised.
14And if Christ has not been raised, our preaching is worthless, and so is your faith.
15In that case, we are also exposed as false witnesses about God. For we have testified about God that He raised Christ from the dead, but He did not raise Him if in fact the dead are not raised.
16For if the dead are not raised, then not even Christ has been raised.
17And if Christ has not been raised, your faith is futile; you are still in your sins.
18Then those also who have fallen asleep in Christ have perished.
19If our hope in Christ is for this life alone, we are to be pitied more than all men.
20But Christ has indeed been raised from the dead, the firstfruits of those who have fallen asleep.
21For since death came through a man, the resurrection of the dead comes also through a man.
22For as in Adam all die, so in Christ all will be made alive.
23But each in his own turn: Christ the firstfruits; then at His coming, those who belong to Him.
24Then the end will come, when He hands over the kingdom to God the Father after He has destroyed all dominion, authority, and power.
25For He must reign until He has put all His enemies under His feet.
26The last enemy to be destroyed is death.
27For “God has put everything under His feet.”
b Now when it says that everything has been put under Him, this clearly does not include the One who put everything under Him.
28And when all things have been subjected to Him, then the Son Himself will be made subject to Him who put all things under Him, so that God may be all in all.
29If these things are not so, what will those do who are baptized for the dead? If the dead are not raised at all, why are people baptized for them?
30And why do we endanger ourselves every hour?
31I face death every day, brothers, as surely as I boast about you in Christ Jesus our Lord.
32If I fought wild beasts in Ephesus for human motives, what did I gain? If the dead are not raised,
“Let us eat and drink,
for tomorrow we die.”
c
33Do not be deceived: “Bad company corrupts good character.”
d 34Sober up as you ought, and stop sinning; for some of you are ignorant of God. I say this to your shame.