Side effect of Czech package? [closed]

Question

Since I need to show a character in Czech, I use the following:

\usepackage[czech]{babel}

This makes everthing looks good including the Czech character, except for the following line showing unexpected result in the generated .pdf:

\usepackage[toc,page]{appendix}
(skip)
\begin{appendices}

becomes like below instead of printing "APPENDICES":

P RÍLOHA A

Any solution idea is appreciated.

Answer 1

Self response. Inspired by hint given by @David Carlisle, removing the usepackage phrase and adding the following line was enough for me.

\usepackage[utf8]{inputenc}

As I updated the original question, the issue occurred at the expressiong that is based on certain package. Thus I still don't know what the root cause is, nor whether the issue is associated with Czech package either.