There shall be a provision as follows:

“Proofs of Loss: Written proof of loss must be furnished to the insurer at its office in case of claim for loss for which this policy provides periodic payment contingent upon continuing loss within 90 days after the termination of the period for which the insurer is liable and in case of claim for any other loss within 90 days after the date of that loss. Failure to furnish proof within the time required shall not invalidate or reduce a claim if it was not reasonably possible to give proof within that time, provided that the proof is furnished as soon as reasonably possible and in no event, except in the absence of legal capacity, later than one year from the time proof is otherwise required.”