Sounds like what would happen if you did 'stty erase "("' [such as in your .profile].

Modern command shells will accept ^H for backspace even if you use such a command to say you want it otherwise.

If this is the problem, then you can fix it (temporarily) by typing 'stty erase ^V' then your preferred backspace key (where you type that control character, not the ^ character). Note how the shell 'protecting' you from this misconfiguration makes it more difficult to correct it.

Then search for 'stty' commands in your ~/.* files for a more permanent fix.

I couldn't think of a way to bring this back to being Perl-related so I downvoted your question. I hope you consider that a fair trade in exchange for the information I provided. Feel free to return the favor.

Good luck.