Cannot lol that particular notification the backend notification toggle is turn ON and grey out for turn off lol. Meaning they force it alway on
I think it will go away if got ignored. A few times downloaded the ota update but did not reboot immediately as battery low need to wait for charging complete. Got notification to reboot. One hour later unlocked phone the notification gone and the updater show no new update.

Need to wait few days or weeks later for the server to push the update to my phone again.
Then xiaomi update server usually will push smaller few hundred MB OTA recovery rom. If missed the first push, the update server will then push the larger few GB full recovery rom the 2nd time.
Go to the updater setting turn off download and update automatically.
POCO M5 – Global Stable
Lstest : V14.0.7.0.TLUMIXM(History)
MIUI : 14
Android : 13.0Update at2023-05-21 17:46:15
Changelog : Expand Official Link
Recovery : miui_ROCKGlobal_V14.0.7.0.TLUMIXM_b16d8555c3_13.0.zip
Filesize : 3.4G
MD5 : b16d8555c31114af93b425314e125252
OTA : miui-blockota-rock_global-V14.0.6.0.TLUMIXM-V14.0.7.0.TLUMIXM-53a6ec0f91-13.0.zip
apply for : V14.0.6.0.TLUMIXM
Filesize : 364M
MD5 : 53a6ec0f9173c95ad15a57fa4586866e
Fastboot : rock_global_images_V14.0.7.0.TLUMIXM_20230508.0000.00_13.0_global_a508bc807e.tgz
Filesize : 6.06G