What device are you using? Are you using a single device with the server at the moment?
The reason for your problem might be different, but I had faced similar problem in the past.
My SIM Telco Operator if my credit balanace is below 0.02 In such case data(gprs) will not work consistently.
hi anton, i am using android mobile and single device at a moment
Traccar Client buffers data if there is no internet connection, so you might be receiving data from earlier.
hi,
i have installed the traccar in amazon ec2. i am able to vie my device in it but the is around 17 min delay in display or tracking