The latest data from an ongoing survey shows that, compared to three months ago, fewer iPhone users are still using Apple Pay and fewer are interested in trying out the mobile payments service than before.

The survey, carried out by InfoScout with help from PYMNTS.com, found that the number of Apple Pay users who had tried the service declined from 15.1 percent in March to 13.1 percent in June. In addition, when asked “Did you use Apple Pay on this transaction,” only 23 percent answered yes, compared to 39.3 percent three months earlier.

“As more and more people buy iPhone 6’s we are seeing a lower percentage of them adopting or trying Apple Pay,” said Jared Schrieber, CEO of InfoScout. “That shouldn’t necessarily be a surprise as we move from people who are early adopters and more likely to try things, to later adopters who are not.”

The survey uncovered a few factors that are likely contributing to the seemingly negative results. Security seems to be chief among these, with 19 percent of respondents in June not using Apple Pay over security concerns, compared to 15 percent in March.

Additionally, it seems more users have had a bad experience using Apple Pay. Four percent of respondents said they don’t use Apple Pay out of fear that it might not work, up from just one percent in March.

If the survey results are anything to go by, Apple also needs to do more to educate iPhone users on how to use Apple Pay. The portion of iPhone users who have not used Apple Pay because they simply do not know how it works increased from 31 percent to 34 percent over the three-month period.

On the upside, Apple Pay users who use the service “whenever they remember” increased from 34 percent to 42 percent.

Despite these results, Apple Pay continues to expand with over 400 financial institutions across the U.S. now supporting the service. In addition, Apple recently kicked off international expansion by rolling out Apple Pay in the U.K. with participation from major banks and around 250,000 retail locations, including Transport for London.

The service is tipped to launch in Canada next.

Image via apple.com