In McEnroe vs Nastasi, why was Nastasi Defaulted by the Ref, then later reinstated? ?

Question

The game took place in late 70s, I was young and didn't understand what happened.

Answer 1

i wasn't even born!!

but i found this:

Ille Nastase 1979 U.S. Open — In a match against John McEnroe, Nastase, in his waning years as a tennis star, turned the competition into a spectacle by constantly berating the head umpire.  Nastase argued frequently until he finally defaulted — only to be reinstated by tournament director Bill Talbert, who feared a default could have caused a riot among members of a festive (and in some cases lubricated) crowd and replaced Frank Hammond in the chair.