Wifi desapears when sleep mode

Please post the terminal output of

sudo lshw -C network

here to show us which driver is used.

You could try the solutions mentioned here:

A script that is launched after suspend or the commands

sudo modprobe -r mt7921e && sudo modprobe mt7921e

(you can test if they work after suspend to activate the wlan. If yes, add them to autostart - create a launcher with these commands.

Or add the kernel parameter
mem_sleep_default=deep
to file
/etc/default/grub