Hello

1. Clear Cache & Data – Go to Settings > Apps > Careers360 > Storage > Clear Cache.

2. Update or Reinstall – Check for updates or reinstall the Careers360 app.

3. Redownload PDF – The file might be corrupt , try downloading again.

4. Convert Format – Use online PDF converters if it's not opening.

check given link

https://engineering.careers360.com/download/ebooks/jee-main-important-formulas

hope this helps you .