Stacking ports will not return to Ethernet on N1148P-ON

I'm very new to managed switches, so please be kind...

I have a stack of two N1148P-ON, running firmware 6.7.1.22 (Just upgraded to try to fix this issue)

They are ring stacked using ports Te1/0/25-6 and Te2/0/25-6

I am using ports Te1/0/27-8 as 10G Ethernet with no issues, but cannot use Te2/0/27 or Te2/0/28

This morning I identified that ports Te2/0/25-8 all identified as stack ports, although I could not seem to use the web interface to change  back to Ethernet as the apply button seems not to save the settings.

I eventually managed to use the command "stack-port Te2/0/27 ethernet" to reconfigure Te2/0/27 & Te2/0/28 as ethernet, which is shown in the web interface, but I am still not getting traffic from vlan1 to these ports.

I am also getting the following errors in the console

""

<186> Mar 28 14:41:25 192.168.100.253-1 STACKING[spmTask]: spm.c(1504) 1765 %% CRIT Multiple consecutive errors detected on stack-port Te2/0/27 (oldRxErrors = 5366 currentRxErrors = 6469 oldTxErrors = 0 currentTxErrors = 0). Please fix the errors before proceeding. The errors would likely be resolved by changing stack cables

""

""

console#/mnt/fastpath/user-apps/hiveagent_pr: error while loading shared libraries: libssl.so.1.0.0: cannot open shared object file: No such file or directory

<187> Mar 28 15:07:14 192.168.100.253-1 OpEN[tRpcsrv.01001]: openapi_logging.c(1297) 2191 %% ERR SUPPORT-ASSIST: Unable to resolve hostname: 'stor.g3.ph.dell.com'.

""

So even though the web interface is showing the port as ethernet I believe the switch still thinks Te2/0/27 is a stacking port.

just a point that is likely linked, I have two vlans, vlan1 and vlan10, ports Te2/0/27-28 show as 'F' for vlan1 while ports Te1/0/27-28 show as 'U' vlan10 only has membership of Te2/0/1-24 and is not required to be stacked.

Any suggestions please?

Jon