NOK 5G21 Gateway Battery Backup

Spent 2 hours getting to a tech rep who didn't understand the problem and said it would take "a long time" to get a sup.  Asked for a call back - none. 5 hours later called back and got a rep who said she would connect me- 20 minutes later she connected me back to the original wait que 😠

So I assume this is still a known issue (lost my internet today briefly during a power failure) - so I was trying to find out if tmo will send a backup battery or if I have to buy my own.

Any help?