Constant Disconnections

Hi,
Was trying to run my Chess Club students through "Checkmate Patterns" today and well kept disconnecting constantly. Other websites were fine, it was just lichess.org.
Is there some restriction on number of sessions from the same IP address restricting us or something?
Time of issue was 3pm to 4pm 19/8/19 AEST (We're UTC +10) & my school IP address is 124.158.21.226.
Thanks.

If many connect from the same site it might get caught by the automatic DDOS protection. If you are doing large tournaments or classes from one spot make sure you get the IP whitelisted. Prolly the easiest way to do this is to explain your situation and include your IP in an email to contact@lichess.org.