Kiva announced a new policy regarding inactive accounts:

So, later this month, we’ll be rolling out a new policy where credit that has been inactive for 12 months will turn into a donation to Kiva. This way, the funds will be put to use helping Kiva fulfill our philanthropic mission, and affected lenders will receive something of value – a tax receipt for a charitable donation.

Kiva says most lenders will not be affected, because lenders with active loans or those who logged in or received a repayment within the last 12 months are not inactive.

Update Dec, 13th: Long discussion by lenders about the proposed change here.