Yes we have restrictions in getAllRecords of all our APIs where you can only fetch 100 records however if you want to fetch all the records, you have to use paging methods to navigate in chunk of 100 or less records. This is being done to make responsive client as well as servers if records are high in numbers. This is the scalable solution if you have more records in your service.
Requesting you to please use paging methods to fetch all your records chunk wise and let me know if you need any help to implement it. Please find a link to get the files using paging method.
Thanks,
Himanshu Sharma