Bilaspur district (Chhattisgarh) boundary centroid from Bhuvan API:
https://bhuvan.nrsc.gov.in/nhpds/get-district-boundary/Chhattisgarh/Bilaspur
centroid_lat=22.404881731703362
centroid_lon=82.07740358305686

Query endpoint:
POST https://bhuvan.nrsc.gov.in/nhpds/get-pixel-value-standardized-runoff-index-annual-cumulative
body={"lat":22.404881731703362,"lon":82.07740358305686}

Requested dates and exact pixel_val (raw) + displayed value (3 decimals):
20170815 0.47819410922649536 0.478
20180515 -0.06189069082522518 -0.062
20180615 0.8723723401543159 0.872
20190815 0.08268964020217753 0.083
20190930 1.5442294359363433 1.544
20210115 0.8260812175564586 0.826