Update modem firmware in teltonika rut955

Im trying to update the modem firmware (EC25-EU) in my RUT955, and it feels like ive tried everything.
Teltonika told me to use modem_updater, but it constantly fails.
I also tried dfota but it says that no updates are available. I havent updated a modem firmware before so all of this is new to me. Anyone have any suggestions on how i could go about updating the firmware?