Looks to me like the male spade connector has broken off. You could try soldering a new spade to the end of the sensor, or simply buy a new sensor. A quick look on Ebay shows the sensor as having a male threaded pillar, so the design might have changed since my car was made.

See CVH Temp Sender


Tim H.
1986 4/4 VVTi Sport, 2002 LR Defender, 2022 Mini Cooper SE