[Bug] Error on user edit page ( only production )

[Vinicius CZB]

User edit page does not work in production

https://gamou.herokuapp.com/users/edit

I believe it's a string concatenation error in Heroku

Heroku log:

2021-08-07T23:17:30.532220+00:00 app[web.1]: I, [2021-08-07T23:17:30.532164 #4]  INFO -- : [a224b3ed-d579-45b2-8622-de0b87ad87c5] Completed 500 Internal Server Error in 53ms (ActiveRecord: 2.2ms | Allocations: 4749)
2021-08-07T23:17:30.535026+00:00 app[web.1]: F, [2021-08-07T23:17:30.534965 #4] FATAL -- : [a224b3ed-d579-45b2-8622-de0b87ad87c5]   
2021-08-07T23:17:30.535034+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5] ActionView::Template::Error (no implicit conversion of nil into String):
2021-08-07T23:17:30.535035+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5]     46:             </div>
2021-08-07T23:17:30.535035+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5]     47:             <div class="form-group">
2021-08-07T23:17:30.535036+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5]     48:               <p class="leading-relaxed mt-1 mb-4 text-blueGray-500">
2021-08-07T23:17:30.535037+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5]     49:                 <% plan = 'web.user.plan.' + current_user.plan + '.title' %>
2021-08-07T23:17:30.535037+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5]     50:                 <%= I18n.t plan %>
2021-08-07T23:17:30.535038+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5]     51:               </p>
2021-08-07T23:17:30.535038+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5]     52:             </div>
2021-08-07T23:17:30.535039+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5]   
2021-08-07T23:17:30.535039+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5] app/views/devise/registrations/edit.html.erb:49:in `+'
2021-08-07T23:17:30.535040+00:00 app[web.1]: [a224b3ed-d579-45b2-8622-de0b87ad87c5] app/views/devise/registrations/edit.html.erb:49