Message app (QKSMS fork) does not work on Xiaomi whyred

I have a Xiaomi Redmi Note 5 (codename "whyred") https://en.wikipedia.org/wiki/Redmi_Note_5

(IIUC, the "Message" app is a fork of QKSMS.) QKSMS has issues receiving SMS on the official ROM. "Message" has issues both receiving and sending SMS on /e/

See my bug report upstream: https://github.com/moezbhatti/qksms/issues/945

1. I can receive MMS; but 72 hours later, I get a notification that the MMS couldn't be delivered, and is available to download from a web server.

2. Sending MMS always fails