After Paul's introduction to a letter, he usually includes a thanksgiving prayer. However, in the letter to the Galatians, that does not happen. Instead, he opens with astonishment and rebuke over the situation in Galatia. Let's read Galatians 1:6-10. I will bold the main points to look back after reading and follow the flow of the passage.
"6 I am amazed that you are so quickly turning away from him who called you by the grace of Christ and are turning to a different gospel—7 not that there is another gospel, but there are some who are troubling you and want to distort the gospel of Christ. 8 But even if we or an angel from heaven should preach to you a gospel contrary to what we have preached to you, a curse be on him! 9 As we have said before, I now say again: If anyone is preaching to you a gospel contrary to what you received, a curse be on him! 10 For am I now trying to persuade people, or God? Or am I striving to please people? If I were still trying to please people, I would not be a servant of Christ." (CSB).