How to use --since option with docker logs command

Please refer to the Docker docs.

docker logs --since 1h

The --since option shows only the container logs generated after a given date. You can specify the date as an RFC 3339 date, a UNIX timestamp, or a Go duration string (e.g. 1m30s, 3h). Besides RFC3339 date format you may also use RFC3339Nano, 2006-01-02T15:04:05, 2006-01-02T15:04:05.999999999, 2006-01-02Z07:00, and 2006-01-02.

as the help says

--since string Show logs since timestamp (e.g. 2013-01-02T13:23:37) or relative (e.g. 42m for 42 minutes

I would do

docker logs mycontainer_or_id --since 60m

This syntax is correct according to my active container