I got this issue as well, first 3 commanders, Raynor, Kerrigan and Artanis, are capped at lev 5.
Just like everyone else on this forum, my commander Raynor is capped at level 5. It happened a couple days ago and when I log in i get an error message saying I can’t make a proper connection to the blizzard servers. It only appears briefly before I get into the game.
Yeah the same thing happened with the same exact characters
As I posted in another thread a few days ago:
Similar issue for me:
Coop commanders levels were reverted to 5 for the 3 basic commanders. My Raynor, Kerrigan, and Artanis commanders were all level 15, prestige level 0. Today when I logged on, I noticed they are all level 5, still prestige level 0. It appears as though they were reverted to level 5 (perhaps because because they are “free to play” & not purchased then that was later fixed since they are the default commanders, but the levels remain lost).
No change since that post.
Raynor suddenly capped level 5 and cannot progress. Previously lvl 15 with prestige level 1
Same here logged in today and it says I haven’t purchased Raynor and my level was reset to 5, and wont progress to 6…
same my kerrigan back to lvl 5 i was lvl 67
Same here. My free to play coop heroes’ (Raynor and Artanis) levels have been dropped down to 5, and are capped regardless of which mission I complete.
same issue with raynor and artanis
i got some problem pls help me
Same issue with raynor, full prestige lvl 15 reseted to lvl 5, can select perks, cant level him up
Raynor, Kerrigan, Artanis, are all lvl 5 once again for me as well. It looks like they still have the prestige categories I already unlocked. They were level 15 at least on February 7th, the latest co-op replay i have available. I am unsure when this data flip-flopped. I noticed that when I first load the game there is unusual lag connecting to the BNet servers, and then the “connecting to Blizzard Services” dialog box shows up telling me the game is awaing a response from the Blizzard Services - and that the service may be temporarily unavailable or my internet connection may be down - which I checked, I am online! This disappears within 3 seconds and i am connected, it shows all my achievements and progress for the campaigns. Swann, Vorazun, Karax, and Stukov are all still level 15 and the other free to play are all capped at 5 as i expect them to be. Kagara is unaffected but i never got her past level 5. Level 83 Co-Op 
- I tried the “Scan and Repair” option from the BNet desktop app but it tells me everything is fine.
My Artanis was at Level 9. I was working towards another prestige, but he’s at level 5 and I’m getting the same message about needing to purchase the commander to advance past level 5.
My Raynor, Kerrigan and Artanis are all lvl 5 to me and it’s like locked.
That’s insane, help us Blizzard.
my Raynor, Kerrigan and Artanis are back to lvl 5.
+1
“Post must be at least 20 characters.”
+1 same issue on all the commanders
Raynor, Kerrigan and Artanis have been reset to level 5.
+1 same issue on all the commanders
my karagen,reynor and artanis where set to level 5 and i cant even level them up