squid.conf overwrites my custom lines of configurations after reboots.

[Toxsickcity]

Can I request Squid plugin have a field to add custom lines, or a way to adjust expiry of items in the cache.

things like big videos, exe files and archives, I would like to have my cache accessible without updates for at last 30 days..
I have tried adding these lines but they delete after router reboot.

refresh_pattern \.exe$ 1440 90% 43200
refresh_pattern \.zip$ 1440 90% 43200
refresh_pattern \.7z$ 1440 90% 43200
refresh_pattern \.rar$ 1440 90% 43200
refresh_pattern \.mp4$ 1440 90% 43200
refresh_pattern \.mkv$ 1440 90% 43200

I may be doing this wrong and would appreciate alternative options.
It appears my cache seems to redownload items at speed for only approx 12-24 hours.even after reboots so the proxy is working. I would like the files to download from cache for at least 30 days.