Echo is the reflection of sound waves. We can hear every echo but we can’t hear each reflection of sound. so we can say that every echo is reflection of sound , but every reflection of sound is not an echo.

Sir/madam you have written that there is no difference but there is difference between the both the difference is given below:
Yes there is difference between echo and reflection of sound
when sound is incident on the surface of a medium it bounces back into the first medium this phenomenon is called reflection of sound but now if we apply some conditions on reflection of sound then it will become echo the conditions are:
1.Distance btw the listner and reflective surface should be at least 17m.
2.Time difference btw original sound and echo must be 0.1s.
so from above we can define echo as:The repetition of sound caused by reflection of sound after applying some conditions on reflction of sound is called echo
ECHO is part of reflection and every echo is reflection but every reflection is not echo.
I hope you will understand my answer
-Devlflowe HJ.

we don't really need the first condition though but other than that, you're argument made a ton of thing clearer

Right