You need all of your K-1s (unless you have this documented elsewhere) to calculate your basis.
Your basis is increased and decreased by certain items (see link below for list).
https://www.irs.gov/publications/p541#en_US_202102_publink1000104288
A basis worksheet is available at the link below.
https://www.irs.gov/pub/irs-pdf/i1065sk1.pdf
