Except to the extent approved in writing by Buyer, no Seller has waived the performance by the Underlying Repurchase Counterparty of any action, if the Underlying Repurchase Counterparty’s failure to perform such action would cause the Underlying Repurchase Transaction to be in default in any material respect nor, except to the extent approved in writing by Buyer, has any Seller waived any such default resulting from any action or inaction by the Underlying Repurchase Counterparty.