If the available and undisbursed amount on the platform and the total donated amount have decreased, it means that a donor has requested a refund.
For example:
Total amount donated to the campaign: EUR 10,000
Available and undisbursed amount in the campaign: EUR 3,000
A donor requests a refund of their donation of EUR 1,000
Then the amounts shall be as follows:
Total amount donated to the campaign: EUR 9,000
Available and undisbursed amount in the campaign: EUR 2,000