Paul followed their advice, though he probably knew it would not successfully present problems with the Jewish population. In doing this he was not compromising his principles, nor admitting that giving of offerings was of effect, but instead following what he had already stated in 1 Corinthians 9.20.

If Jesus took away sacrifices in the temple, why did Paul continue to give offerings?

Acts 21:26 Then Paul took the men, and the next day he purified himself along with them and went into the temple, giving notice when the days of purification would be fulfilled and the offering presented for each one of them.