Can not upload video to Peertube

Hi. I’m running a private Peertube instance. One problem I am encountering is that I can not upload videos that are bigger than 1.5MB from my computer. The loading bar stops at one point though I try to upload a 21MB video several times. Sometimes, it loaded to 100% but stops at processing status. Import by URL is still working fine.

Does anyone know what is happening or have the same issue?