Can you give me best reply to thank you letter received from association for giving them assistance/support?

Question

Can you give me best reply to thank you letter received from association for giving them assistance/support?

Answer 1

Just a simple reply stating you have received their letter and will respond with more help when you can ~~

Answer 2

There is no need to reply. Assistance and support were  offered and a thank you was extended it. You do not reply to a "thank you" because it then falls to the other group to thank you for thanking them for their thank you . . . . So you just accept the thank you for a job well done. That would be the proper end of the cycle of communication.