After undoing the sending of a message, it is no longer possible to send it later.

Steps to reproduce

1. Click on answer a mail message.
2. Write something in the mail message.
3. Click on send.
4. Click on undo sending
5. Click on send message later and pick a date

Expected behavior

The message can be sent as desired.

Actual behavior

Nothing happens when I click on “send later.” The message cannot be sent. I think it's the same if you normally send the message, but I couldn't test that.

Mail app version

5.1.4

Nextcloud version

31.0.5

Mailserver or service

No response

Operating system

No response

PHP engine version

PHP 8.3

Nextcloud memory caching

No response

Web server

Apache (supported)

Database

MariaDB

Additional info

JS console error:

[ERROR] mail: could not send message 
Object { app: "mail", uid: "example_user", level: 2, error: {…} }
​
app: "mail"
​
error: Object { message: "Request failed with status code 404", name: "AxiosError", code: "ERR_BAD_REQUEST", … }
​​
code: "ERR_BAD_REQUEST"
​​
config: Object { timeout: 0, xsrfCookieName: "XSRF-TOKEN", xsrfHeaderName: "X-XSRF-TOKEN", … }
​​
message: "Request failed with status code 404"
​​
name: "AxiosError"
​​
request: XMLHttpRequest { readyState: 4, timeout: 0, withCredentials: false, … }
​​
response: Object { data: {…}, status: 404, statusText: "", … }
​​
stack: "je@/apps/mail/js/mail.js?v=46e943a6-137:2:1072151\nf@/apps/mail/js/mail.js?v=46e943a6-137:2:1076435\n"
​​
status: 404
​​
<prototype>: Object { constructor: J(e, t, n, a, r), toJSON: toJSON(), stack: "", … }
​
level: 2
​
uid: "example_user"
​
<prototype>: Object { … }
index.mjs:54:16
    log index.mjs:54
    error index.mjs:72
    default NewMessageModal.vue:479
    a match.js:15
    onSend NewMessageModal.vue:468