Test multiple power banks in multiple slots, to make sure the base is the issue.
If ZERO slots are charging the power banks, the issue is likely your AC adapter.
If only SOME slots are charging power banks, the issue is likely the base.
If you suspect the issue is the base, and your Collins is within its warranty period, submit a warranty claim and we'll get back to you. Do not send your Collins to us until we have asked for it.
If your Collins is outside its warranty, you can purchase a new unit from our website.