<p>The teachers are correct … it they submitted their recommendation letter online, they can’t change that online letter. The easiest answer for you for the rest of your applications is to select a new different teacher for future schools that you want to apply. It sounds like you can re-use the other teachers letter for the rest of your applications, and if you need an add’l recommendation for other schools, ask a 3rd teacher, which you can then select for the schools that need 2. </p>
<p>The alternative is to still use that teacher’s recommendation and hope that other schools are too offended that they were not your first choice.</p>