Sunsynk server only recording in 5min interval
Sunsynk are apparently doing some maintenance on their servers.
Even if you have the update interval set to be every 60 seconds, the data graphs and historical data will only be recorded in 5min increments.
This is a change that Sunsynk has temporarily implemented.
Below is the Sunsynk App customer service response:

76 Views

I had exactly the same. Reverted back to 5min intervals at 1320 on the 27th of September. Been querying at regular intervals ever since and getting the same response.