"Internal Server Error" when sending message

Support
1

The image shows a forum page with a pop-up window displaying an "Internal Server Error" message, interrupting the view of a support petition for funds. (Captioned by AI)
The image shows a forum page with a pop-up window displaying an "Internal Server Error" message, interrupting the view of a support petition for funds. (Captioned by AI)1339×1498 150 KB

It says “Internal Server Error” when sending a message to someone with these console logs:

XHRPOST
https://biohacking.forum/posts
[HTTP/2 500  343ms]

	
POST
	https://biohacking.forum/posts
Status
500
VersionHTTP/2
Transferred1.21 kB (46 B size)
Referrer Policystrict-origin-when-cross-origin
DNS ResolutionSystem

PLUGIN discourse-multilingual] Deprecation notice: Importing getOwner from `discourse/lib/get-owner` is deprecated. See the alternatives on meta. [deprecated since Discourse 3.2] [deprecation id: discourse.get-owner-with-fallback] [info: https://meta.discourse.org/t/292080]

Anyone know why it would randomly show a 500 error when just sending a normal message?