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There is a communication pause with Voyager 2 since July 21, the antenna points 2 degrees away from Earth. A series of planned commands sent to NASA’s Voyager 2 inadvertently changed the antenna alignment.

Source Mission Update: Voyager 2 Communications Pause

How large is the beam width compared to the 2 degrees miss-alignment?

GrapefruitIsAwesome
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Uwe
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    https://descanso.jpl.nasa.gov/DPSummary/Descanso4--Voyager_new.pdf. 0.5°. Just providing the link for those who want to make it a full answer – asdfex Jul 30 '23 at 17:59
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    FWIW, from Voyager 2's perspective, the Earth's orbit is currently around 1° wide. https://i.stack.imgur.com/CPzYx.png The time step in that plot is 3 days, with 60 days between numeric labels. – PM 2Ring Aug 01 '23 at 07:15

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According to Wikipedia https://en.wikipedia.org/wiki/Parabolic_antenna the half-power beam width for a 3.7m diameter antennae (like Voyager 2) with X-band transmission at 3.6cm would be 0.60 degrees.

Voyager 2 also has S-band communications at 13cm which would have a half-power beam width of 2.5 degrees using the same parabolic reflector.

Woody
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    But is S-band downlink still possible over the huge distance from Voyager 2 to Earth? Antenna gain 36 dB for S-band is much smaller than 48 dB for X-band. S-band seems to be used only after launch but not nowadays. – Uwe Jul 31 '23 at 16:16
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    Sounds like a new question. @Roger Wood is very knowledgeable on Voyager communications. – Woody Jul 31 '23 at 17:23
  • Doesn't Voyager only use S-band for uplink? X-Band is for downlink and irrelevant here, because earth needs to upload the corrected navigation commands, not download anything. – Rainer P. Aug 07 '23 at 11:35