Electric guitar pickup not picking up a specific string

Question

Just string an old guitar with Fender's pure nickel wound 009 gauge. I don't have any prior knowledge whether the pickup is faulty or not. The issue is the B string not picked up by the guitar pickup. Things that I've tried;

1. Putting e or any other string which is not B on B string spot, the string will get picked up just fine.
2. Putting the B string on any other spot does not make it got picked up by the guitar.
3. Tried using a different amps with combination above, still the same result.
4. Tried using new string (still same brand), same result.

I have limited experience with the instrument. I don't know if it is the pickups fault or the B string is not actually a nickel wound. Does faulty pickup usually just fail to pickup a specific string or a specific string spot? or both?

Right now I'm considering checking the pickup's configuration, wiring and what not. No prior experience so I would like some feedback on where I should start. Try a different string set/brand?

Thank you for your time.

Answer 1

Since you've updated to show that the B-string you are trying does not get picked up in any string position, it's almost certain that whatever you have for a B-string does not contain magnetic material. Chuck it and buy a new B-string.