Debezium stops after initial sync - postgresql

Question

The initial sync works as expected but then the connector just stops and does not care about further table changes. There are no errors thrown and the connector is still marked as active and running.
Database: Amazon Postgres v10.7
Debezium config:
"name": "postgres_cdc",
"config": {
"connector.class": "io.debezium.connector.postgresql.PostgresConnector",
"database.hostname": "...",
"database.port": "5432",
"database.user": "...",
"database.password": "...",
"database.dbname": "...",
"database.server.name": "...",
"table.whitelist": "public.table1,public.table2,public.table3",
"plugin.name": "pgoutput",
"key.converter": "org.apache.kafka.connect.storage.StringConverter",
"value.converter": "org.apache.kafka.connect.json.JsonConverter",
"value.converter.schemas.enable": "false",
"transforms": "unwrap, route, extractId",
"transforms.unwrap.type": "io.debezium.transforms.ExtractNewRecordState",
"transforms.unwrap.drop.tombstones": false,
"transforms.route.type": "org.apache.kafka.connect.transforms.RegexRouter",
"transforms.route.regex": "[^.]+\\.[^.]+\\.(.+)",
"transforms.route.replacement": "postgres_$1",
"transforms.extractId.type": "org.apache.kafka.connect.transforms.ExtractField$Key",
"transforms.extractId.field": "id"
}
}
Any thoughts about what the problem could be?
Edit:
Log-Errors:
ERROR WorkerSourceTask{id=postgres_cdc-0} Failed to flush, timed out while waiting for producer to flush outstanding 75687 messages (org.apache.kafka.connect.runtime.WorkerSourceTask)
ERROR WorkerSourceTask{id=postgres_cdc-0} Failed to commit offsets (org.apache.kafka.connect.runtime.SourceTaskOffsetCommitter)