group leader, seniors and the summon master can fix this. if you are any of these, go inside your group base and click at Fukasaku NPC. click the Group Summons option

from there you will find an empty space option you can click it and consume the amount of chakra that your summons need to consume.

if the limit is at 75% for example, you will need to add 2500 chakra to make it 100%