I reached out to my supplier with my case and was strongly supported by him and Teltonika support in the background to solve the issue. I received two FW test versions for analysis and returned the dumps.
In the end it turned out to be a defective hardware and I was sent an exchange device immediately and asked to return the defective one afterwards.
My issue was solved in very reasonable time of a few days with both my supplier and Teltonika showing great motivation in trying to help me with my problem!
Thanks guys!
why all defective around the same time. Certainly seems fw related to me and from the logs.