You need to specify the version in the mount options, did you that?
user=username,pass=password,vers=2.1
If that doesn't work, it might be the old version in OpenPLi 4 doesn't support it yet. I've tested the current develop version, and that works fine with SMB version 2.1, so the problem will be addressed soon.
And most NAS systems support NFS, so you could switch to that. It will be faster than CIFS as well.
Currently in use: VU+ Duo 4K (2xFBC S2), VU+ Solo 4K (1xFBC S2), uClan Usytm 4K Ultimate (S2+T2), Octagon SF8008 (S2+T2), Zgemma H9.2H (S2+T2)
Due to my bad health, I will not be very active at times and may be slow to respond. I will not read the forum or PM on a regular basis.
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