I have an Instagram account about nightlife.

I created this business account (from scratch) about a month ago. Of the 40 posts I made, I have promoted 10 of them. Each was 6 euro in total for 3 days. I focused my promotion to a few if the big cities in the UK only.

I get hundreds of likes but no one actually subscribes. Right now I have 35 subscribers and most of them are people I know personally. I think about 6 people subscribed because of my promotion.

I know it's only a month but I expected more of an increase of subscribers.

Do I need to invest more money per post? More patience? How long would something take? Anything else?

Many thanks in advance.