Linear Opener Questions

Hello Group, I just found this forum and hope that someone in here can help me. I have a Three year old Linear Opener that does not work all the time. When it acts up it raises the door about 6" then stops. I have to close the door and hit the remote again and it goes all the way. It started doing this less than 6 months after the company installed the news door and opener. They came out and replaced the mother board saying that will fix it.   Well that only worked until it went off warranty. Here we are three years later and I have had it. I have called Linear directly and they said to replace the mother board. I told them it already has been and then they said well replace it again. I asked if they would cover it and they said NO. I need this fixed ASAP. I have watched many videos only to see that nobody covers this issue.  Is there anyone that can help me?  I'm a very handy guy and can figure out just about anything but this really has me stumped. HELP ! !

Hey everyone, Well I ended up removing the cover of the Linear Opener and found quite a bit of sawdust in it. I am a woodworker but didn't realize how much dust would get inside this. Anyways I blew it all out and then I unplugged it for about an hour. Plugged it back in and it's been working fine ever since. I don't know if the dust was doing it or if it just needed to be rebooted for that hour. It's been a week so far. If anything changes I'll let you all know. Thanks for looking at this .