Citizens of different countries have the facility to enter Sri Lanka through the process of ETA, which makes it easier for tourists as well as businessmen to enter into Sri Lanka. Through the process of Sri Lanka ETA application, people from authorized areas can obtain their approval through the Internet before coming to Sri Lanka.
Which countries are eligible for Sri Lanka ETA?

Most nations are eligible to submit an application for the travel authorization electronically, ETA for short-term trips to Sri Lanka. Singapore, Maldives, and Seychelles are exempted from the process. But there are a few nations where citizens cannot submit their applications on their own and need to obtain their visas before landing at the embassy of Sri Lanka. The vast majority of travelers need to confirm the rules from the official website regarding Eligible Countries for Sri Lanka ETA.
What are the common reasons for Sri Lanka ETA rejection?

The main causes for rejection of Sri Lanka ETA applications are easily avoidable errors. The most common cause is a typo error, including typos in the applicant’s name or passport number. The ETA process also rejects applications where the applicant’s passport is valid for fewer than six months after their arrival in the destination country. Other reasons include failure to demonstrate proof of a return flight ticket, lack of sufficient money to support the stay, visa overstay history, or poorly taken photos.
Are there special ETA rules for diplomatic passport holders?
Yes, there are some special rules about the ETA which are applicable to diplomats carrying diplomatic passports, but only depending on where they are going to travel to. For example, within the framework of ETIAS in Europe, diplomats do not have to apply for an ETA in most cases. On the other hand, Canadians need to apply for an ETA, if they are visa-exempt diplomats, but not accredited diplomats in Canada. Therefore, it all depends on where one is going to travel, their citizenship, and the purpose of the trip.