Upload stops after few files are uploaded and starts again

When I’m trying to upload multiple(say 200) files to next cloud through my Desktop Application certain(10-12 files) amount of files are uploading and upload stops for a while for like 10-12 Mins and resumes itself again. Tried every solution found on google but can’t find any solution to the problem. Any help suggestion regarding what can be done OR what could be going wrong would be really appreciated.

What I have noticed so far is that whenever I send a request to read file after upload is complete it usually stops uploading and won’t proceed for few minutes.

I’m using multi-threading to make various requests like creating folder, uploading chunks of files to server, reading files(Read file information) from server, etc. I’m making webDav requests to server which make use of PROPFIND, PROPPATCH methods.

I’ve tried sending requests to server through Postman. Requests made through postman didn’t take time. Please let me know if more information is needed to understand issue.