It looks like TMDb (https://www.themoviedb.org), which is where SeriesGuide gets movie data from (and also the “New episodes” section for shows), is currently blocked by some Indian internet service providers (ISP).
If you are affected please talk to your ISP to help out TMDb! Details in the tweet below:
A workaround might be to use another network connection, like mobile data or to use a VPN that exits in another country. This may allow circumventing the block of TMDb.