Codex cannot edit a file

Question

### What version of Codex is running?

codex-cli 0.63.0

### What subscription do you have?

PLUS

### Which model were you using?

gpt-5.1-codex-max

### What platform is your computer?

Linux 4.18.0-477.15.1.el8_8.x86_64 x86_64 x86_64

### What issue are you seeing?

it just simply cannot edit any file without shell command

```
› Modify testfile.txt by appending one line: "modified by codex".
  Do not run any shell commands. Make a direct patch. Only touch this file.
```

a command like this