Thanks you and @ChrisRahme very much for your answers.
Switching between forms in the financial bot using conditions and saving previous form seems great if I can get it to work with my own case. I will try that.
Dynamic behavior could work as well and is actually my personal favorite but since my form A is decision tree like form, where each new question depends on previous answer, it is already a bit complicated (specially for non-coders in the team), mixing it with another form might get it too complicated and hard to maintain. Specially since form B can be called using other means as well.