Issue with constraints inside a UITableViewCell - ios

Question

I have a custom cell for a UITableView. I'd like the following elements inside the cell:
1) UITextView with the following constraints:
it starts at the top left corner of the cell
it goes from the left side of the cell + 10 until the right side of the cell - 10.
its bottom should be 5 points above the next element (see 2 below)
2) UIButton with the following constraints:
it is X and Y centered in the cell
it goes from the left side of the cell + 20 until the right side of
the cell - 20.
it has a height of 60
The cell itself is defined with a height of 100.
However it seems my constraints have some conflicts according to the errors I get but I don't see where. Here is my code:
// constraints for the UIButton
answerTextButton.heightAnchor.constraint(equalToConstant: 60).isActive = true
answerTextButton.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 20).isActive = true
answerTextButton.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -20).isActive = true
answerTextButton.centerXAnchor.constraint(equalTo: centerXAnchor).isActive = true
answerTextButton.centerYAnchor.constraint(equalTo: centerYAnchor).isActive = true
// constraints for the UITextView
answerTextView.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 10).isActive = true
answerTextView.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -10).isActive = true
answerTextView.topAnchor.constraint(equalTo: topAnchor).isActive = true
answerTextView.bottomAnchor.constraint(equalTo: answerTextButton.topAnchor, constant: -5).isActive = true
What's the conflict here?
Thanks.
EDIT : I don't believe my mistake. While you are all right that the X-center constraint is useless, it was not the issue. The issue was... that I forgot to add "answerTextView.translatesAutoresizingMaskIntoConstraints = false".
Sorry for that, never happened before! So basically all my constraints for the UITextView were messy because of that. Adding it fixed everything but I kept your recommendation by removing the X-center constraint on the UIButton.

Answer 1

Copy and paste. It will work
// constraints for the UIButton
answerTextButton.heightAnchor.constraint(equalToConstant: 60).isActive = true
answerTextButton.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 20).isActive = true
answerTextButton.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -20).isActive = true
answerTextButton.centerYAnchor.constraint(equalTo: centerYAnchor).isActive = true
// constraints for the UITextView
answerTextView.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 10).isActive = true
answerTextView.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -10).isActive = true
answerTextView.topAnchor.constraint(equalTo: topAnchor).isActive = true
answerTextView.bottomAnchor.constraint(equalTo: answerTextButton.topAnchor, constant: -5).isActive = true