ews attachment size limit on exchange 2013

While restoring a mail with attachment equal or more than 13 mb , mail restore fails . We use netbackup to restore individual mails and we use ews . We want to increase the limit of the attachment . we referred the article "https://video2.skills-academy.com/en-us/exchange/configure-client-specific-message-size-limits-exchange-2013-help" web.config already shows the "maxAllowedContentLength="67108864"" bust still we get an error while restore all mail with attachment below 13mb restores just fine .. we want to know what is the default limit for attachments in ews and also need to know how to increase it. another question is what is the difference between attachment limit in outlook and ews