Quota
There is a Quota implemented in terms of the number of entities that you can fetch during a period of 24 hours. An entity is for example one Visit, Branch, or Service etc. The quota is implemented to protect the system from being overloaded. The current quota is 5 000 000 entities per 24 hours. If you exceed the quota, you will need to wait until the quota is reset. 5 000 000 entities should be enough to pull all your data in a 24 hour period.