Yes, this can happen for several reasons. These discrepancies are only temporary and will only apply to historical documents copied to Inly during your migration. Going forward using Inly, the income number will perfectly represent your earnings.
A pending bill may have been paid through your old CRM in the intervening time since your migration. When this happens, you can update this in Inly by clicking on the corresponding invoice and selecting, "Add offline payment."
For historical documents migrated from other CRMs, the Inly income number will reflect what you billed. Income numbers from other CRMs may be factoring in a loss from credit card fees. Future income through Inly will calculate for those fees.
We migrate the most recent calendar year of your projects. In your former CRM, payments that you invoiced in the prior year may have landed in this year and would therefore appear in your income number in your old CRM.
Your old CRM number may be including tips you received from old projects. Tips received through Inly will be counted going forward.