Research shows that there isn’t a contradiction in the following two accounts depicting Saul of Tarsus’ encounter with Jesus’ voice on Damascus Rd:

Acts 9: 7 says that those accompanying Saul heard the voice that spoke to him. Acts 22: 9 says those with Saul saw the vision of light that he did, but they heard not the voice that spoke to him.

In the Greek, the words that are translated into “heard” and “voice” have two meanings: (1) sound or tone, (2) words or message.

Consequently, in Acts 9: 7, it is saying that those with Saul heard only the sound of Jesus voice, but in Acts 22: 9, they did not hear (comprehend) the sound as words in Jesus’ message to Saul.