There are various reasons why this can happen.
Check in your Batlogger Connect account if cloud sync is turned on:

If you have a gold subscription, you get 5GB data transfer over LTE every month. If you record more than 5GB in a month, it will be uploaded in the next month.

In this example, you start with an empty BATLOGGER WE X and record 3GB in April. All those recordings are uploaded to the cloud.
In May you record 7GB. Only 5GB of this will be uploaded. 2GB will be stored on the internal SSD and are uploaded in June.
Older files will be uploaded first.
If your cloud storage is full, no files will be uploaded until there is new space available in the cloud. Download the files and delete them from the cloud.
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