4G sub modems for slate plus?

Hello,
I tried to use my Slate plus with my Huawei 3372H SUB modem but unfortunately it doesn't work.
Does anyone have a any suggestion about a compatible USB 4g stick?

Hi,

May I know if your 3372 can switch to HiLink mode through the APP?
Please let me know the detail model, take a photo for device sticker.

No it doesn't.
It's the "router" model. So, when I plug it to my PC it's shows as "eth".

I know that Flint 2 sees the stick, although I didn't use it. But now I need a 4G sub stick that works with the Slate Plus, I will travel in September and I need one ASAP.

Here you refer: