Hi,
An external data which is 3rd party data provided by vendor has been added over a Sharepoint page in a scripteditor webpart. Unfortunately, it stopped working since a week. The issue is very inconsistent and if regreshed multiple times it gets opened and viceversa. Attached is the error screenshot. There has been no activity done on our Sharepoint servers like patching. Also there is a strange issue that it works with in server and outside of server it works only for few.

Also it is a vendor data, so we have very limited access to it. We just inserted the given Iframe code in a scripteditor webpart. We dont have access to edit or remove data.
Can someone kindly help me on this?
Regards,
Susmitha.