Gateway timeout in SAP Data Hub 1.0 SPS 3 trail version

Hello experts,

Could you please help with the following issue about Data Hub?

I am facing the error of gateway timeout when opening Data Hub Cockpit with tab Landscape and Discovery. I am using the trail version for 1.0 SPS 3.

This issue has lasted for a long time(more than one week) and I've tried to suspend and reactivate the instance several times but it didn't help at all.

Also, following the note 2602716 - Release Restrictions for SAP Data Hub 1.0 SPS 03,

"Non reachable HANA systems cause Cockpit Overview and Landscape to timeout

When a HANA connection was created, and the HANA instance might not responding (due to error), the Data Hub Cockpit might receive a gateway timeout when calling Data Hub Objectservice by /v1/systems. This behavior does not occur on first creation of HANA connection, but might happen, when HANA DB is not reachable after creation."

I can connect to HANA DB with SYSTEM user on HANA studio during the whole time.

As for the "flow agent" mentioned in other place, it also looks good from my point of view and was not deleted.

I don't want to delete the instance and work with a new one as I've already built some models and data inside the current one.

Any clues are welcomed or could you please tell me where I can get some direct help?

Thanks in advance.