You can say no or not + a/an/any There is NO problem = There isn't (is NOT) A problem. There are NO oranges = There aren't (are NOT) ANY oranges. There is NO time = There isn't (is NOT) ANY time.

Carmen, Here is a short explanation using the negative form of the “there is” construction. The explanation doesn’t cover all the possible meanings and uses of the adjective “no”. You can say or write— 1) - There isn’t a problem. This means that a problem does not exist. Don’t forget the article with countable nouns. - There aren’t problems. This means that problems don’t exist. When speaking if you stress the indefinite article ‘a’, the meaning changes. - There isn’t A problem. This means that there isn’t just one problem, there are several problems. So to avoid this misinterpretation you can write or say—not any. 2) -There isn’t any problem. or - There aren’t any problems. This means that there is not even one problem. Another way to say 2) is to use the adjective ‘no’. 3) - There is no problem. - There are no problems. This means the same as 2) not any. There is not even one problem. ‘No’ and ‘not any’ can also be use for uncountable nouns with the meaning of “no amount”. There is no time. There isn’t any time. There is no money in my bank account. There isn’t any money….

You cannot say "There isn't problem". Isn't = is not. After, not and before a singular countable noun, you must say 'a/an'. There isn't A problem.

Very Interesting Question , but haven not answer.