toddler's anxiety about strangers

[MyBigShoutingDay]

My DD is 21 months old. She's very confident with family members and my friends who she sees regularly but has always been more hesitant with people she doesn't know well. Recently this has got much worse, particularly with men. She just seems so frightened

She goes to nursery 2 days a week and is fine there (no men though) and is used to being with other family members apart from me and DH.

I just wondered if anyone had any experience of this and ideas how I can ride it out? She seems like she has more of a cautious personality type and that's fine, but I'm hoping this fearfulness is a phase???

The things I'm doing at the mo are:
Reassuring DD by holding/cuddling her but not making a big deal of her crying or being upset.
Carrying on talking to the adult normally.
Asking adults to give her time and let her come to them (some people are better than others at this!).

Any other ideas or experiences much appreciated. TIA

[MyBigShoutingDay]

No one???