Dream order questions: pgp encryption, vendor communications

Hey, guys! I know these are noob questions, so please forgive me in advance. But:

1. Would it be bad to check Encrypt for Dream's built-in encryption tool on top of sending a previously-encrypted message (encrypted via tail's built-in pgp applet)? I kinda did this so wanna make sure it was ok

2. Is it normal for a vendor to ask for an address again after it was already sent?

3. Is dream's built-in encrypt tool enough or should I just use the pgp encrypt from tails and never bother with Dream encrypt?

4. How many times can I fuck up encrypt until the vendor just rejects my order? I want to add an "lol" but really, it's a serious question