8.3(2). The contract partner/participant will only be entitled to exercise further warranty rights (termination, reduction, compensation for damages) if the remedy in an  individual case is negligently omitted or is impossible or unsuccessful despite several attempts. All claims – particularly warranty claims – against Pro+Motion GmbH will  become unenforceable due to lapse of time in one year counting from when the claim arose and in cases in which Pro+Motion GmbH acts as a travel organiser from the end of  the event as scheduled in the contract. Pro+Motion GmbH’s services include some for whose performance it depends on the cooperation of public authorities, e.g. to procure  visas. In such cases, Pro+Motion GmbH will not owe successful performance, but will only owe the effort to procure it. This applies to the extent that Pro+Motion GmbH is not responsible for the reasons preventing success. The efforts of Pro+Motion GmbH/expenses incurred by Pro+Motion GmbH as a result must be remunerated by the contract partner.