Issue with Unix timestamps (converting time columns failed: failed to convert time column: column type "[]*string" is not convertible to time.Time")

Hi,
thank you for reading the post.
I have the following issue that the postgres request executed by Grafana does not work and gives some conversioning error. (See below the sgl_raw-request and the error-message in the response of the Grafana postgres request). I checked the raw request used by Grafana with the postgres client pgAdmin, where it is working fine and you can see the output in the picture.

Has someone an idea what is going wrong? Thank you very much.

The error message from grafana:
“converting time columns failed: failed to convert time column: column type “*string” is not convertible to time.Time”