NR5307 5G Router "Why is it so difficult to have the latest firmware?"

Good day to all. I live in Greece. I got the NR5307 5G Router from Central Europe seller via Ebay, because it is not commercially available in Greece. I always check to see if there is newer firmware, for security reasons. In this page:

https://support.zyxel.eu/hc/en-us/articles/21131267341842--SA-Zyxel-Security-Advisory-security-advisory-for-buffer-overflow-vulnerabilityin-some-5G-NR-CPE-DSL-Ethernet-CPE-fiber-ONT-WiFi-extender-and-securityrouter-devices#01J6VM1ZHY64DS1W9SFQJB212A

I found out that there was newer firmware than mine

1.00(ACJT.0)B6 (new one)

V1.00(ACOM.0)b1 (my firmware)

The OTA function in the router does not work, it gives an error.

In the support web page above, it says that I should ask for the firmware from my local company that supports and imports ZYXEL products (https://www.digitalsima.gr/).

I sent them an email, they immediately responded and asked me the serial number and the place I bought this router from. I told them the truth, they never responded back and they never gave me the file….

I would be very obliged if someone can send me a real link to the file…georgiadis.m@gmail.com

It should not be that difficult…

Thank you in advance.