it looks like you’re using the iOS app. i have only the Android app, which shows observation count but not species count by user on the project page. what i see in Android is 1220 observations for you, which matches what shows up on the website’s project page.
so the fact that you get 1239 (19 more observations) suggests to me that probably the iOS app is including observations where the geoprivacy (or taxon geoprivacy) are set to obscured or private, whereas the website does not.
you can confirm this by looking at the Explore page in the website to see what your observation count and species count are. that page should also include your obscured and private observations – so it should match the counts from the iOS app when you are viewing it from your account.
if this is in fact the source of the discrepancy, i can’t tell you for sure whether or not the project page behavior (excluding obscured / private observations) on the website (and maybe Android) is intentional or not. someone from staff would have to make that determination, i think.