JMeter extracted value disappeared after the next sample

JMeter extracted value disappeared after the next sample

Hi: Newbie to JMeter here. I have been successful in using Regular
Expression Extractor but my problem is the extracted value reverted to the
default value after the next sample. E.g., I successfully extracted the
value to "Mytoken" from sample 1, this is proven by the Debug sampler as
well as using it immediately in the next sample. However, when I tried to
reference "Mytoken" again a couple samples later, the value is replaced
with my default value. How can I keep the value extracted to stay for the
whole thread?
HT