We had a BSNL Broadband connection a years back and had to face several problems.
First, link failure was almost a daily issue.
Also, we were billed doubly once - the connection we had was a one-year package payable each year, however we were billed twice in that year.
BSNL’s landline service is equally bad.
First, it is costly compared to mobile phones.
Also, the staff at the branch offices tend to make people run around for everything - for example they do not say clearly which documents are required for termination of connection on death of original owner and confuse people as to which documents are actually required.
Bad experience.