Hello Alito14,
It sounds as though you’re having issues charging your MagSafe Battery Pack, but you’re able to charge your iPhone with the battery pack.
Apple Support Communities is a fantastic place for help! To confirm, have you reviewed the following article? It provides some great information that may help with resolving the issue you’re facing.
How to use your MagSafe Battery Pack
If reviewing the tips and information in that article doesn’t help, the next step would be to contact Apple. You can find their contact details via the Get Support website
Take care!