Hi @Iwona1
There are a few ways you can upload receipts to the receipt hub, including emailing them and integrating Dropbox.
When emailing, there is a limit on the size of the attachments you can upload per day, for more information, please see the following: Email us your receipts
When integrating Dropbox there is the same daily limit as emailing, for more information, please see the following: Dropbox integration setup
I hope this helps, but if you have any further questions, please don’t hesitate to ask.