Solicitor has been "running searches" for 6 weeks now

Our solicitor said searches would take 2-3 weeks. It's been 6 weeks. Every time I chase, I get a different excuse — "the council is slow", "we're waiting on one more result", "it should be any day now".

Our seller is getting impatient and threatening to put it back on the market. I'm paying this solicitor £1,400 + VAT and I can't even get a straight answer about when things will be done.

Is this normal?? Should I switch solicitors at this point?