"...to have been" or "... to having been"?

When I help someone and the person thanks me, instead of saying "You're welcome", I want to express that "I am happy that I was able to help you", but I want to say it with a much shorter phrase.

I came up with this:

Happy to have/having been able to help

But I'm not sure which of the usages of have after to is correct.

Here are the correct forms.

• Happy to have been able to help
• Happy of having been able to help

In the same vein, you'll find the following, which you might prefer; "having been" is not used much and possibly not at all in speaking. Here is an ngram showing that "happy of having been" is not found and that "glad of having been" is rare (probably only found in books).

• (I'm) Happy/glad to have been of some help to you.
• (I'm) Happy/glad that I have been of some help to you.