Issue when creating more than 3 rows

Hello,

i tried to create a new tipboard dashboard with more than 3 rows.

details:
page_title: Test Dashboard DB Modular Cloud
layout:
- row_1_of_4:
- col_1_of_3:
- tile_template: big_value
tile_id: running_ec2s
title: Running EC2
classes:

- col_1_of_3:
- tile_template: big_value
tile_id: stopped_ec2s
title: Stopped EC2
classes:

- col_1_of_3:
- tile_template: big_value
tile_id: failed_ec2s
title: Failed EC2
classes:

- row_1_of_4:
- col_1_of_3:
- tile_template: big_value
tile_id: running_rds
title: Running RDS
classes:

- col_1_of_3:
- tile_template: big_value
tile_id: stopped_rds
title: Stopped RDS
classes:

- col_1_of_3:
- tile_template: big_value
tile_id: failed_rds
title: Failed RDS
classes:

- row_1_of_4:
- col_1_of_2:
- tile_template: big_value
tile_id: running_ssm_agent
title: Running SSM Agents
classes:

- col_1_of_2:
- tile_template: big_value
tile_id: conn_lost_ssm
title: SSM Agents - Connection Lost
classes:

- row_1_of_4:
- col_1_of_2:
- tile_template: big_value
tile_id: 2running_ssm_agent
title: Running SSM Agents
classes:

- col_1_of_2:
- tile_template: big_value
tile_id: 2conn_lost_ssm
title: SSM Agents - Connection Lost
classes:

When i am using 3 rows then everything is fine and the dashboard is being displaying correctly. However when I am using 4 rows as stated above then all I see is a black screen but no tiles are being rendered.

Can you have a closer look at this?