Contributing private capital

I have a yarn shop. When I order from my wholesaler, I always have to buy more than what customers buy. They buy per ball of yarn and I buy per pack of yarn. Sometimes the purchases are therefore greater than the income. To bridge this gap in my first year (= stock build-up), I regularly invest my own capital into the professional account. Is this also considered start-up capital or how exactly should I contribute this? I assume this also goes through income? I read in the learning center that it is best to enter a comment for start-up capital and record this, but what exactly should the comment say, because for me this is no longer start-up capital but rather stock build-up. Can you please help me? Thanks in advance. Els