have you updated EFI/BIOS recently? maybe S3 sleep is not supported on your system anymore and instead you get suspend-to-idle as S0ix (Modern Standby) notoriously shitty under linux. sometimes you can flip it back in EFI/BIOS
If you’re ok with signup by phone number (can be burner phone number), Telegram and Signal are options. Depending on country, if you’re unlucky you’d need to cycle through a few numbers that works for Telegram, Signal has no such problems