Yes, this problem has already happened before to someone else here. Here's the link to the thread - you can find potential solutions there.
Sorry that Instagram stories and posts have become problematic for you; that can be especially disorienting when work-related needs come into play. While I cannot offer an exact solution, here are a few suggestions you could try:
Update Instagram: Always install the most up-to-date version of Instagram onto your device to avoid incompatibilities and compatibility issues with third party apps and services.
Clear App Cache: Navigating to your phone settings, finding Instagram app and clearing its cache may help resolve temporary glitches or any corrupted data issues that arise from use.
Check your Internet Connection: A poor Internet connection may lead to problems when uploading images, so try switching networks or switching over to Wi-Fi connection to see if the issue persists.
Use A Different Device: If possible, try uploading stories and posts using another device in order to see if the problem still occurs on that one or if it applies across accounts altogether. This could help narrow down if it is unique to one particular account or device.
If none of these steps work to address your problem, Instagram support might need to be reached out again. Please bear in mind they receive many inquiries at once so it could take them some time to reply.