What would get someone banned from Venmo?

I've been banned from Cashapp and PayPal for unknown reasons. Just woke up and saw and email saying that I couldn't use my accounts anymore.

I only used Cashapp for the cash card and whenever friends wanted to split lunch or something like concerts. PayPal I had it for similar things, but somehow a "transaction" I made either went wrong or the system flagged it and I was banned or permanently limited.

I have like 3 friends on Venmo and I use this platform rarely, but now I'll use it more frequently since it's all I have left, but I'm worried that I'll use a wrong card or something and get banned.

What reasons would I have to worry? I've seen people on Reddit and other places say that they get banned for adding weird notes to their transfers, all I use are the default emojis that are on there.

Thanks in advance.