gosh that was a small pot . I suspect the plant was too small. when it starts into growth next spring give it regular feeds [or put slow release fertilizer pellets in the top couple of cm/inches of the soil. they will flower when they get mature enough.

Eileen is on point. Agapanthus often don't bloom the first year. This is one of the most rewarding and trouble-free plants you can ever grow. Typically they start blooming in June and continue on through Fall. I just placed an order myself for delivery in early Spring.

Refer to this article as a checklist of other reasons why Agapanthus won't bloom. Knowledge is power.

Non-Blooming Agapanthus Plants – Reasons For Agapanthus Not Flowering

https://www.gardeningknowhow.com/ornamental/bulbs/agapanthus/agapanthus-not-flowering.htm