Making more than one umrah

Assallamu allaykum. Respected Mufti,

1) Can one make more than one Umrah and

2) What should one do if ones hair is already cut off after performing a first Umrah?

3) Can one go to Masjid Taneem as a Meeqat for a second Umrah?

4) And lastly can one wear sandals while making Sa’ee of Saffa and Marwa?

Jazakhallahu khayr