What do you do when your SaaS app is growing slower?

My SaaS app is a plugin for online stores. And I'm the solo founder working on it right now.

After Easter, the installation growth rate is slower. I think the slow growth is probably due to this seasonal factor.

I just wonder what other SaaS founders do when the growth rate is slower? Marketing? Talking to customers (Try to reduce churn)? Optimizing the system performance (To cope with high season)?