Solo 401k funds held at Wells Fargo... inactivity is a problem?

[David Orr]

I have a solo 401(k) and the funds are held in a business checking account in the trust's name at Wells Fargo.  Apparently Wells Fargo is the most popular bank to use for this.  

I just found out that if I don't make a transaction at least once every 60 days, they may make the account "dormant" for inactivity.  How do people deal with that issue with a 401(k) since only certain transactions are allowed?  It's been about 60 days, and I'm getting ready to write a check for an investment, but the check could get returned if they happen to make the account "dormant" just before it clears.  

In a similar issue, they already closed one of my two accounts (one is for Roth 401k funds and one is traditional) because it was inactive for a few months and had a zero balance.  They didn't even notify me, they just closed it and never told me.