wrong output for 0,00.0000000000000000000000000a formatting

So I tried numeral(30).format('0,00.0000000000000000000000000a') and answer is '29.9999999999999964472863212'

surprisingly when I add one more zero to formatting the answer is correct. numeral(30).format('0,00.00000000000000000000000000a') '30.00000000000000000000000000'

please fix this issue.