Hi,
This error usually occurs when a transaction is waiting for a resource which is already locked by some other transaction.
First of all, after this error occurs, you should run
SHOW ENGINE INNODB STATUS in order to get more information. Link:
SHOW ENGINE INNODB STATUS[
^]
Let me know the results.
Also, you should consider increasing the default (50 seconds) lock wait timeout value. Link:
innodb_lock_wait_timeout[
^]