Sapporo festival in early July?

Helloes!
I noticed when checking my reservation on a Toyoko Inn hotel in Sapporo in early june that most of the rooms have been fully booked from 2nd to 7th July. Around that dates it seems more unbooked.

Is there any kind of festival or something going on during that time? I could only find information on the Sapporo Jazz party but it is during a more widespread period than just those days.

Is it because of the Furano flower fields or Asahikawa hiking?

I think you also know, Hokkaido tourist destination in summer very popular.
Be the same as other tourist destination, it is a fully booked in on Saturday night in many cases. As it is considered, because it is the marathon at Sapporo Dome on July 6, there may be the effect.
Perhaps, I guess you did a search of a continuous stay their website. If it is a weekday, there should be a vacancy.
It is possible to you, only July 5, I think it would be find Hotels other than Toyoko Inn, or, Accommodation in Sapporo other.

Toyoko Inn Sapporo-eki Kita-guchi Calender
https://yoyaku.4and5.com/reserve/html/rvpc_rfrncClndrMnth.html?clndrDa...

Minami-guchi Calender
https://yoyaku.4and5.com/reserve/html/rvpc_rfrncClndrMnth.html?clndrDa...