Jmeter regularly extracts some characters in the return parameter

1. The information returned by the interface is as follows:

{"data":{"id":"fs-onclick_TVdObU1UT**rTjJSak1EZGs="},"success":true}

2. jmeter regular extraction

Regular expression "id": "fs-onclick_(.*?)"

Final extraction part: TVdObU1UT**rTjJSak1EZGs=