So you need to make the axle hole bigger without removing the tongue.
You need to be brave and move the tongue around with enough force that
compresses the fibres in the axle hole enough to give a bit more clearance
in there. Bend the tongue back clear of the body and force it from side to
side a bit, press down in the tongue, pushing it into the jack body, then
pull it up, pressing the fibres in the hole away from the axle.
Believe it or not you CAN overdo this; firm but not violent.
Subject: sticky tongues
I have a couple of lazy tongues, that go back so slowly that the note won't
repeat. The cause of this laziness is not the bristle. So, what can I do to
improve the repetition? If I take the jack out and move the tongue back and
forth for a minute or so, it behaves better, but only for a very short
time. The tongue can't be removed easily from the jack, since the pin
doesn't go all the way through.