Everyone gets a writers block. Everyone. Even the great ones. There are different tactics you can find on the internet to unleash the writer in you, but here is an easy one for your MUN:Planet contributions.
Try answering a question first.
Questions are usually direct and focused. More importantly, a question naturally already has an audience of listeners (well at least - an audience > 0).
The trick here is to take an interesting question that has a few people following it, and create a post around it. For example, here are a few questions you can turn into posts:
Answer a question above, but then create a longer piece around it. Do 30 min of research and find the best possible answer with videos or images. If you expanded the initial focus of the question, be sure to add the relevant topics so that your piece can reach an even greater audience.
How is that for curing your writers block? Simple, but effective.Writing is a muscle. Exercise it.