Git fix accidently amended commit

Scenario:
Need to update a public method "strToNum()".
The key command:

git reset --soft xxx

Steps:

1. Checkout master, pull the lastest changes:

git switch master; git pull
// Say the latest commit is "add support s support"

2. Create a new branch and make changes:

git swtich -c fixBugxxx
// Make some chnages to "strToNum()" and add a new test case, say "strToNumTest02()"
git add -u
git commit -m "Update strToNum() to fix bug xxx"

The issue is: when I add a new test case, I accidently wrote a wrong test case, which will absolutely fail.
And we have a git hook to run test cases every time when we add a new commit:

$ cat .git/hooks/pre-commit
#!/bin/sh
./gradlew check

So the git commit command fails.

3. I fixed the test case strToNumTest02(), and try to amend the changes to the earlier commit "Update strToNum() to fix bug xxx".
   Which leads to the issue, I thought the changes will be amended to Update strToNum() to fix bug xxx, but actually they are amended to the earlier commit add support s support.

// Update strToNumTest02()
git add -u
git commit --amend --no-edit

4. So I need to restore my branch fixBugxxx to align with the master, and save the changes to a new commit

git status // Check if it's clean
git reset --soft origin/master
git diff --cached // Double check the changes to be committed
git commit -m "Update strToNum() to fix bug xxx"
git push -u origin fixBugxxx

5. Make a MR in the remote repository.

And it's fixed.
The key command:

git reset --soft xxx