Sharing the below for the benefit of other community members, If any one is facing the same issue I would suggest you take a look into the below checks
- Could you please check whether all the packages/libraries that were running in local are deployed to azure or not.
- while the application is running are observing any high CPU or memory usage issues?
- On which app service plan you are application is running (like free or shared etc.,)
- Since each and every webapp runs on a sandbox environment we have couple of restrictions and pdf generators which were developed on these frameworks (Syncfusion,Siberix,Spire.PDF).
I have found these documentations from Iron Pdf and also this SO thread you can take a look which might be helpful
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