Could have been the spray you used. Labels have known to be wrong....

Cut it back and fertilize it wit a nice organic fertilizer and keep it well watered.

Was the can an aerosol? If so, the propellant can "freeze" plant tissues it's too close to.

Actually, I shouldn't have said can. It was a plastic bottle that you hook up to the hose. It's a concentrate of sorts.

Spraying an entire garden for bugs can be extremely detrimental. One should always spot treat for a specific problem rather than randomly poisoning an entire garden. Many chemicals can cause damage in heat/sun/drought when they might not at other times of the year.

Look up clematis wilt. I had it happen once and what a shocker it was. Good news, the plant sends up healthy new growth.

With dark purple blooms chances are it is a Type III and they usually don't wilt. Six year old Clems usually don't wilt either it is a problem of newly planted Clematis.

If it was problem with the spray, do you think it will come back this or next year?

Also, thanks much for your responses and support.

The only way to know is to cut it back and fertilize it and keep it well watered. If it is just cosmetic damage it should pop back this year.