In such reversionary annuity contracts there shall be a provision that the contract may be reinstated at any time within three years from the date of default in making stipulated payments to the insurer, upon production of evidence of insurability satisfactory to the insurer, and upon condition that all overdue payments and any indebtedness to the insurer on account of the contract be paid, or, within the limits permitted by the then cash values of the contract, reinstated, with interest as to both payment and indebtedness at a rate to be specified in the contract but not exceeding 6 percent per annum compounded annually.