All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
There is no doubt that supporting Islam is an Islamic obligation, and this kind of support could not be achieved at the required level except through a collective effort. An individual or some dispersed individuals could not bear this burden.
That’s why collective work is important and required in order to support Islam through Ahlus-Sunnah groups that are active on the Islamic level, but the following matters should be met:
Firstly, it is not an obligation for a Muslim to be affiliated with one of these groups.
Secondly, a Muslim's loyalty to a group should not be such that it divides him/her from other Muslims. The call is for unity within Ahlus-Sunnah, and it should not be in group membership.
Thirdly, these groups are on righteousness but commit mistakes; so we should help them in righteousness and good, and advise them about the mistakes. The truth (righteousness) and falsehood are known when balanced against the Book of Allah and the Sunnah of the Prophet according the understanding of the righteous predecessors among the companions and those who followed them exactly in faith.
So, what is in accordance with this is acceptable and what is not in accordance with it is rejected.
For more benefit, please refer to Fataawa 2496, 22613, 33503, and 351652.
Allah knows best.