Custom GPT kept freezing indefinitely during response

I am not sure if this is just me, or something that is experienced by everyone?

My custom GPT kept freezing, whenever I ask it a question regarding the files in the knowledge base. (around few thousand pages of pdf files)
Just to be more specific, by freezing, I mean: I send GPT a question, GPT starts to respond, then few sentences later it stops in middle of a sentence and regardless how long I waited, it just freezes there.

I encountered the same problem at least ten times per day for the last two months, OpenAI support offered no solution, but I kinda got used to it. The work around that I found was to force close the entire web browser and restart the web browser again, it would work for maybe around two questions, then it freezes again. (I noticed the GPT tab will use up all of my memory) Then, I will just delete the entire conversation and start again. It worked before mid June.

Now, regardless what I do, it will always freeze at the first question. I am at a dead end. (but weird enough, GPT tab no longer uses that much memory any more)

what have I tried:
clear cache
clear cookies
force close browser, then restart.

I don’t think this is my computer hardware problem as I can heavily use very hardware demanding programs on my computer without any issue (e.g: Solid Works , After Effects , Premiere pro, etc)
I mainly use a ROG Flow X16 (2023) GV601 laptop with Windows 11 Enterprise installed, not sure if this helps in any diagnoses.
I also use two other windows laptops which encountered the same issue. I also use an Iphone and an Android phone, I noticed when asked the same question, the Iphone and Android phone app will not freeze, but after answering the question in full, CustomGPT will immediately delete its entire response and display an error.

I am really struggling… any help is much appreciated!

Try a smaller PDF just to make sure it’s not some oddball bug with PDFs in general.

Then I would try to make it work with your original file but make it really small.
Then you can try to identify if this is an issue with your file and if it’s a problem with the file’s contents in size specifically.