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You got a thank you call from Jim, the owner of Mainely Tubs. This is your opportunity to call him and see how he will help.I find it hard to believe you got a factory approved fix given your situation. The least they can do is offer you compensation for a spa clearly not up to Watkins standards.
( I was at work when they serviced it )
I would definitely call. Since you were not at home the tech may have simply screwed the original/messed up panel in place until he gets out there with a new panel to install properly. Or he could have done that fix because it was easier than fixing it properly and your call is needed to let them know that's not good enough. Either way, call and ask when the permanent fix will be completed.
Asta, could you post pics of the "fix"? I feel your pain on dealing with things like this. It's so hard to know if we are asking for too much or too little from someone. Best of luck getting things resolved to your satisfaction.